>>34
Heehee, my pic sure is getting around, ain't it. :P
Anyways, I attempted to start an Ork army a while back, but it never really got off the ground, so I can't really talk about strategies and strengths/weaknesses and all that, aside from the obvious.
What I can and WILL say is, if you like converting stuff, Orks are PARADISE.
You can just cut and glue together pretty much anything and it'll look good. You don't need to worry with putty and perfection, because it's SUPPOSED to look makeshift and ramshackle. If you play Space Marines and want a Heavy Bolter, you need to buy one. If you play Orks and want a Big Shoota, just stick a couple of Shootas together! You can scratch-build stuff too pretty easily.
I actually started building a Gargant, but after I abandoned the Orks I turned what I had done of it into some scenery. It's pretty much just a polystyrene base, with parts of pop cans affixed to it with carpet tacks. That's what I mean - converting Ork stuff is really easy, really fun, and turns out looking really good.