Belts are expensive and I never seem to be able to find a nice one in the stores, but lately I've been "finding" lots of belts for free! :) Depending on your sense of style, this can give you some nice belts...

Step 1: What You Need

- A bag (preferable one that is unusable or that you're gonna throw out)
- pants that need a belt
- imagination :)

Step 2: Make Your Belt!

When one of the straps of a bag I used regularly broke (luckily I had two of the same bags), I figured I might as well use it as a belt. The strap itself was intact but one of the clips broke, leaving just an empty ring to put the other clip on. With simply adjusting the strap to fit around my waist I had a belt. :) For extra coolness, this one even had a nice decorative shoulder pad-thingy!
Some people have asked me if it wasn't a hassle with the clips, but it's much easier than a normal belt, since it has one fixed length and all you have to do is clip it on.

Step 3: Improvise

Not every strap is instantly usable as a belt obviously. The one from step 2 had one broken clip, otherwise I had to saw it off or something to use it as a belt. I have 2 other belts, which I got from some old laptop bags we were throwing out at work (IT helpdesk).
One of them (from a leather bag) was instantly usable by just letting the clips grasp each other. The other one had two clips that didn't fit together. My colleague was nice enough to bring a ring from his curtains for me, so with that I had another belt!

I don't know for what sizes this works, since I have a very small size. Part of the belt is doubled up for me though, so I'm hoping this works for more people (in case there are people with an equally weird sense of style who are willing to walk around in this :P).