OOH--another idea--instead of using the oven and risking noxious fumes, how about putting it on foil, and baking it outside in a gas grill? Any risks there I'm just not thinking of? Gas/fume interaction dangers? Heck, you could build a fire on the ground and put it on foil over a grate... Thinking I should scope out eBay for a bunsen burner now...
I think straight heat will just melt them, not crackle them.
Just thought you guys would enjoy this video of a CD in a microwave.....other than the fire, nothing BAD happens! http://video.google.com/videoplay?docid=3587466534692702285&q=genre%3Acomedy&hl=en
The only reason it caught fire was because it was left in there for 35 seconds. You only need about 3 to 5 seconds to make them crackle.