I can't top Sam's gaming gear, but I noticed that the OpenPandora is a glaring omission in his handheld collection. The OpenPandora is an open source (hardware and software) handheld computer running a custom Linux distro for retro gaming. It is arguably the geekiest handheld gaming device ever. I pre-ordered it and waited years before I finally got it because the people making it had no experience running a business, let alone ordering custom parts from China. By that time, there were smart phones with better hardware.
My final project for the BFA show at SAIC was a chaotic number generator that played algorithmic music written in Max/MSP with a physical controller connected to my PC via an Arduino. It played pitches through a software synthesizer and graphed what it played on screen.
Guitars aren't a classic geek clichĂ© but I have so many that it makes me a guitar geek. The best estimate I can make off the top of my head is about 20 guitars, not including the ones that are taken apart. I've built a handful from scratch and heavily modified others. I'm planning on building a series of about 10 over the next year or so.
When it comes to playing guitar, I like technical death metal and jazz fusion but I don't have the time to get my chops up enough to actually play that stuff. If you go to a tech death or fusion show, pretty much the entire audience will be music geeks, and most of those will be guitar geeks.
I started learning HTML in middle school so I could have a website to share movies I'd made in Microsoft 3D Movie Maker. Later on, I had a site for Starcraft maps. In college I tried to write a 2D top down RPG game engine in Python. You could draw walls on the map, walk around, and collision detection even worked, but then I got to the part where I needed to move the camera when you get to the edge of the screen, which screwed up my collision detection and I eventually gave up. I wasn't a very good coder back then.
I'm a member of the American Homebrewer's Association. Like all geek pursuits, brewing is part science and part art. I moved recently so I don't have any homebrew right now, but I try to keep at least one 5gal keg of it in my fridge at all times.
I only watch Star Trek. Watching through Star Trek: Voyager right now, and when I need some casual background noise episode I go to Star Trek: the Next Generation.
I'm a Bitcoin enthusiast. Yesterday I pre-ordered the new Mastodon album with Bitcoin. When Overstock.com started accepting, I ordered some bed sheets because I just had to spend some coin. I own a huge neon sign that says "Bitcoin accepted here" just for apartment decor.
I also mined for a while and still have the three miner rigs in my apartment. I stayed up way past my bedtime trying to tweak them for the best performance. I wrote a real-time market depth chart using the Mt. Gox streaming API. Since Gox went down I haven't hooked it up to another exchange yet. When I lived in a garden apartment, I got flooded and was almost electrocuted pulling the plug on them.
Live long and prosper!