Want to get some great ideas on how to create awesome props without laying out a ton of money? Talk to a low-budget filmmaker. After all, they're trying to accomplish the same thing gamers are- maximizing the audience's ability to suspend disbelief using limited resources.
Head over to The Monkey Rodeo to find some great ideas and inspiration from a guy making a horror film on a shoestring. The particular post I'm linking to has details about some great makeup effects, but if you take a look at the archived posts you'll discover some incredible props, ranging from massive weapons to arcane tablets, made with the simplest of materials.