I'm a big fan of having useless junk around so I think I may just go into this a little bit to explore my custom figurine options...
Now as a dragon enthusiast I have to cover that base first: now I already have a few of Todd McFarlane's dragons, but I wouldn't say no to having a custom one with me being heavily involved in the design process. I also wouldn't object to fellow aspiring concept artist DefiledVisions [http://conceptart.org/forums/showthread.php?t=166495] designing the dragon that they would then turn into the model.
One of my favorite dragons in terms of design, simply because it was one of my first ever dragons, was the version of Smaug from 1976's animated version of The Hobbit. Mid flight and roaring his guts out, hell yeah.
As a rabid Miyazaki fan, I don't think my dragon collection would be complete without Haku's dragon form. Speaking of which, I'd also like a figurines of an Ohmu, the Great Forest Spirit (either in his deer or nightwalker form), Totoro, the Robots from Laputa and Howl's Castle.
I want to have certain figurines from Final Fantasy games, but they never make the ones I'd really want. For example: where is a full on model of Kefka's tower. Not the whole thing, obviously, but a model of the final series of boss fights would be awesome. I also think my dragon collection needs a Bahamut in there somewhere but I don't think they've designed him well very many times. They always seem to make his feet/legs improportionally large. Final Fantasy IX still holds the best design of Bahamut thus far, so I guess that would be cool to have a figurine of.
Speaking of JRPGs and dragons, I want figurines of all the dragons from Chrono Cross to complete my collection.
That covers my dragon bases pretty well, for now so let's take on a different subject...
In terms of anime: I'd want Mugen and Jin figurines from Champloo, as well as a figurine of Phantom Miria from Claymore. Also a model of "The Bebop" from Cowboy Bebop could be potentially sweet.
In terms of other video game-related stuff: This category could go on for so long, but I'll keep it short by mentioning only that I would love figurine of Manny from Grim Fandango, and models of Colossi #s 1, 3, 8, 13 (or 14, whichever was the giant flying serpent).
In terms of movies: I'd love a couple of models of the creatures from Avatar, especially the Ikran. Figurines of all of the Wild Things would be great, though I'd prefer figurines of the original Sendak illustrations than the movie's interpretations (as much as I loved the movie).
That's the short list. I love figurines...