Let's face ituntil they're cooking us breakfast and doing our laundry, the most fun you can have with store-bought robots is the fun you make yourself. Sure, robots like WowWee's Roboraptor (and its companions, Robopet and Robosapien) are surprisingly capable for $60-to-$200 toys, with wide ranges of motion, touch sensors and powerful software. But it's those same out-of-the-box skills that make the 'bots such prime fodder for hackers.

If you're anything like us, you were the type of kid who took apart dad's
new radio just to see what was inside. That kind of curiosity never dies,
which is why How 2.0, PopSci's award-winning home for the coolest
tips, tricks, hacks and do-it-yourself projects, wants to see what today's
tech tinkerers are up to.

Have you built something amazing you'd like to
show off? Tried a How 2.0 project and failed miserably? Blown something up
with the kids' chemistry set? If you've invented it, tweaked it, hacked it,

Make CO2 Ice Cream

Cost: $150
Time: 15 Minutes

Safe | | | | |
Risky

For an illustrated photo how-to, launch the gallery.

Want some real home theater bragging rights? Instead of buying a projector capable of casting a 14-foot image at 1080p (progressive) resolution-the highest high-definition there is-build one yourself. After all, the front projector´s innards are simple: an LCD lit by a superbright lamp, and a few lenses to magnify and sharpen the image. Retail models start at around $800 and use proprietary $400 lamps that burn out every few years. But cheaper lamps work equally well, and none of the other parts are very expensive. Why not put one together yourself?

My mom loves seeing my digital photos, whether they´re of far-off places or my latest culinary creations, so I´ve long thought about building her a digital-photo frame that would show a new shot every time she walked by. But instead of loading 1,000 images onto a hard drive, I wanted to be able to update the library remotely, adding new pics as I shot them, so she could always see what I´d whipped up that night or where I´d traveled that weekend. I also wanted the whole project to be cheap, because, well, I´m cheap.

Specs: Casio EX S600BE

What: Thinnest 6-megapixel camera available


Size: 2.32 in. (h) x 3.54 in. (w) x 0.63 in. (d)


Weight: 4 ounces

Cost: $400