Glues
Sniff it. Inhale it. Breathe it. Noooooo... that's not right. Oh yes: ventilate! If you've started down the path of building your own R2, then you're probably a little crazy and need all the grey matter you've got left. So ventilation is key when playing with these glues. If it can melt plastic, it'll do not nice things to your lungs.
R3-Y2
R3-Y2 had a couple seconds of screen time in ESB.
I've had a lot of fun making this droid. I got to play with him at Star Wars Celebration V, but had to sell him shortly afterwards due to my kid being born. The guy who got it didn't want the dome, so I still have that.
Bicycle Plus a Gas Engine
After reading a particular MAKE Magazine article... I REALLY wanted to strap a small engine to my bicycle. Thus began one of my more mechanical projects.
Hell Boy prop - Reliquary
I was secret Santa for a coworker who's a big Hell Boy fan. I stumbled upon the Hell Boy Reliquary thread at the RPF and it seemed like a perfect gift. Using a bunch of 50% off coupons to Michaels and Jo Anns Fabrics, I bought what I needed.