This pattern came free with the October 2010 issue of Let's Knit magazine, but also comes from the book Crobots by Nelly Pailloux. He's a little bit fiddly using only a 2.5mm hook but the finished result is so worth it. My 2yr old has slept with him on his pillow every night since I made him and we had a little panic at 8pm cos he disappeared (he fell down the back of the bed, but brave Mummy resued him).
I enjoyed him enough to buy the full book and I'm looking forward to making my robot loving 2 year old a few more similar things for his Christmas Stocking substituting embroidery for some of the springs and beads in the patterns. Made exactly to the patterns most of them are not suitable for kids, but perfectly suitable for the geeky friend you have.