If you ask me, focusing in on a single hobby wont get you anywhere. I found that, personally, trying to learn hobbies to achieve a goal, or make something was something that pushed me further than "something to kill time with" or such. Granted, that's simply my experience, and you'll probably differ. （ ´,_ゝ`）

If you just want to make some stuff, Papercraft/origami is inexpensive (just needs a printer), not too hard, and can take up as much space as you like. There are torrents on 4/po/ if you want to give it a shot.