If you are a running enthusiast you’re going to love today’s Brad Feld’s Amazing Deal. Today’s deal takes the barefoot running phenomena to its logical conclusion. Invisible Shoes, created by two former lead designers from Nike and Reebok, are the closest you will ever get to feeling barefoot, even if you aren’t. They’re perfect for running or walking or yoga. Did I mention that you put them together yourself for the perfect fit? Awesomely loving the DIY world.

At $16 (normally up to $35) these are definitely worth a look.

Last week on Brad Feld’s Amazing Deals we offered a huge discount on Ruby classes, and had one of our most successful offers ever. This week I asked my friends at Udemy to cook up another great deal on the course “Creating iPhone Games for Beginners”. They came up with an offer where $39 takes you through the process of building a complete iPhone game (normally $99).

Leave a comment and give me your pitch for a new iPhone game. The best idea by midnight tonight gets a free course.

Today on Brad Feld’s Amazing Deals you can purchase a $250 Ruby course from Udemy for only $49. The course, Learn Ruby Programming (In Ten Easy Steps) contains over 30 video lectures, written course materials, and additional discounts on Ruby literature.

With more and more companies making the move to Ruby on Rails, demand for Ruby developers has gone through the roof. If you are interested in giving Ruby a look, this is a great place to start.

Before we invested in MakerBot, we bought and assembled a Thing-O-Matic. When I say we, I mean me, Jason, and Ross. It took us about 20 hours (Jason and I did the first half; Jason and Ross did the second half) and was a blast – think of it as an adult lego project. Our Thing-O-Matic has been steadily printing stuff – you can play a game of chess with our Thing-O-Matic pieces. the next time you are in my office.

As part of the endless series of Amazing Deals I bring you from my deal site, today’s offer is a fully assembled Thing-O-Matic. If you want your own 3D printer, but you don’t want to assemble it, you can buy it fully assembled for $2,500. But, through the magic of daily deals, there are 20 available for a 20% discount ($2,000). This is a one time offer from my friends at MakerBot so grab ‘em while they are available.

In additional TechStars Cloud launched today along with the first episode of TechStars on Bloomberg TV.

And finally, for all of you that have written asking for a “Convertible Debt Series” like our term sheet series, we’ve just started one on AsktheVC.com. The first post is up and introduces the series – we’ll be working through all of the terms in a convertible debt deal over the next few weeks.

Today on Brad Feld’s Amazing Deals, we’ve got another great offering from our friends at Udemy. For $49 you can get The Lean Startup, The Lean Startup Ignite, and The Lean Startup SXSW by Eric Reis.

These three courses contain over 9 hours of content and 60 talks from people like Eric Ries, Dave McClure, Steve Blank, Hiten Shah and many more. That’s a lot of knowledge for 67% off.

In addition to the courses, you get a hardcover copy of Eric Ries’ awesome new book The Lean Startup. Eric – congrats on converting all of that digital content to ink on dead trees!

Today on Brad Feld’s Amazing Deals, we are featuring the Urban Sherpa Strap from Go Gaga. Sherpa Straps distribute the weight from laptop bags, gym bags, and briefcases that take straps, across your back and shoulders. I’ve been using the Sherpa Strap for a while – it’s dynamite.

With today’s deal, you can get the strap and free shipping for $19, a discount of 50%.

If you have a bag that you love, but are tired of having it cut into your shoulder as you are traveling from DEN to LGA, check out Sherpa Straps. For each purchase, Go Gaga will make a donation to The Mountain Fund, helping some real sherpas.

Also, check out today’s deal deal on your iPhone or Android. Deal Co-op recently launched the Feld Store web app, a full touch site for mobile buyers. Once you store a credit card in your account, you can check out my deals each week on mobile, and buy future deals with one click.

At Brad Feld’s Amazing Deals, we only bring you shiny happy deals. If you are a Mac user and like to live in a mail client instead of a browser, Sparrow Mail is for you. I paid $10 when it came out but through the magic of daily deals am making it available for $5 for the next 24 hours (up to 1000 copies).

Jason Calacanis even loves it – on G+ he says:

“I’m absolutely in love with Sparrow Mail. It’s made me 10-35% faster in GMAIL/Google Apps.”

For the next 24 hours, you can get Sparrow Mail for $5 instead of $10. Just wander over to Brad Feld’s Amazing Deals and grab it. And be able to say “I got something for $5 that Brad paid $10 for that he then made available for $5 bwahahahahaha.”

Today on Brad Feld’s Amazing Deals I’ve got a great offer for anyone with a touchscreen device.

The deal is for Joystickers – sticky arcade buttons you put on your touchscreen to make games easier to play. Joystickers is one of the Excelerate Summer 2011 companies (Excelerate is a TechStars Network member) – I met with them a few weeks ago and loved what they are doing.

You can buy three buttons for $9 (normally $20), or five buttons for $13 (normally $34). My friends at Joystickers have even agreed to throw in free shipping.

Check out a video of these buttons in action and get ready to level up.

Clint Nelson, co-founder of Startup Weekend, is bringing the European tomato-chucking phenomena stateside. Today on Brad Feld’s Amazing Deals, you can get a half price ticket to the innagural Tomato Battle – A Huge Tomato Fight. The event is at Copper Mountain on June 25th. Get there at 1pm for beer and music. Start chucking tomatoes at 3pm. Bring an extra set of clothes.

Your ticket gets you in the event and one free beer. There will be thousands of people and hundreds of thousands of pounds of tomatoes. If you are one of my Boulder readers, or plan on being in the area June 25th, go to Copper Mountain and have a blast throwing tomatoes at people you don’t know.

Absurdity, silliness, and wonderment powers my world!

Microsoft Excel and our brains have a lot in common. We all use them, but only to about 10% capacity.

Today I’m offering a solution on Brad Feld’s Amazing Deals from a startup called Excel Everest. These guys can teach you how to use Excel by offering a 20 hour interactive tutorial on the fine points of spreadsheets. Their class is normally $35, but through the magic of daily deals, I’m bringing it to you for only $14 (PC / Windows only). Think of it as getting a class on Excel from my partner Seth, who is the best Excel god I know, for only $0.70 / hour.

Almost all of us are guilty of firing up a spreadsheet and limiting ourselves to just a few basic functions. Spreadsheet proficiency for $14 seems like a steal to me. Once you make your purchase, just head over to the Excel Everest website, plug in your voucher code, and you’re ready to recalculate your spreadsheet knowledge.