Here is a great concept for a CAPTCHA.

The ROTCAPTCHA (PDF, 1.4MB).

It’s a CAPTCHA based on image orientation.

The ROTCAPTCHA system requires users to adjust randomly rotated images to their upright position. This is a task most people will be familiar with given the state of early digital cameras, etc.

This system has many advantages, such as being language independent and support many input sources.

Brilliant. Why didn’t I think of that? yooouuutuuube.com

Another great use of the useless Twitter is My Tiny Jesus. No explanation as to what it does besides pumping recent Twitts.

That said, anybody using Twitter data is either looking for art or fun. So having no explanation sure fits the bill.

Twitter is not my favourite application as you must know by now, but I am often amazed by the things people come up with using their api. It’s filled with tons and tons of useless information. Brilliant for a weirdo mashup.

I will definitely have a play with the Twitter API myself once I’m done with Digg Mob Talk.

Twittearth was brilliant.

And so was Twistori.

Now be sure to check out My Tiny Jesus.

Pretty cool graphic representation. I actually thought there were more.

An arty party project, featuring scanners, pockets and dodgy russians.

Their DNS is as weird as their idea, so if it doesn’t work give it an hour or two.

Wordle is a pretty slick concept. Silly and art mix well together.

Check out Dave Bollinger’s work.

Design:
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That’s what I would call, Creative.

On this one, the only interaction is with your brain though.

Design:
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