I've been building various models since I was about ten years old, starting w/an 18" AMT TOS Enterprise kit. My dad only supervised the construction of this one and I did the work. It was one of the blue-molded kits, tho wasn't my first Enterprise kit, as my dad had made one (along w/a Klingon battlecruiser) for me when I was like 6 - that got played with a LOT! I think this is what started me in to becoming something of a Tech-Weenie, as I've loved starships, aircraft and vehicles of all sorts ever since, tho mostly stick with SciFi.
I dabbled in WWII armor, aircraft and ships for a while, as that's always been an interest of mine, but SciFi always held my primary interests. I mostly build Star Trek kits these days, concentrating on 1/2500 scale. I like that scale as it allows for a very wide variety of designs on my shelf - I have a Federation Fleet of ships from the Pre-TOS Era thru Post-Nemesis that numbers at right about 90, with a Klingon fleet that's nearly 40 strong. The selection in this scale used to be severely limited, but there are more and more kit makers producing in this scale every year - and not just Federation ships. You can also have some awesome looking starbases/space stations in this scale with a number of ships in orbit. For this aspect of my hobby, I hang out over at The 2500 Page Forums a lot, as there are about 15 or so of us really in to this aspect of the hobby. We're a friendly bunch and are always willing to welcome more folks to our little obsession.
Recently, however, I've somewhat strayed away from my Trek cravings and started obsessing over "Battlestar Galactica" - both the two different television series' and the models. While I have fond memories of TOS and don't really look down on it, I find it's seriously dated - storywise -and prefer watching TNS (The New Series) Galactica if given a choice. However, the ship designs of both series hold up quite well. In fact, the creators for TNS have used a number of TOS designs for the RagTag Fugitive Fleet as it currently exists.
Anyhow, that's where I'm currently at w/the bulk of my building and collecting of models. I still purchase new 1/2500 scale Trek kits and have a small stockpile of those unbuilt. However, I'm always looking for new BSG models, as well as ways to build up those designs from TOS & TNS, as well as making new original designs.
And there you have it. Hope yer eyes didn't glaze over too badly.