I wrote this in another section, but thought it belonged better here so I posted a new thread hoping people would read it and comment on what they thought.
A friend turned me on to some bio-based lubricant called "LubriMagic" all purpose lube and penetrant made by a company called LubriMatic Green. I found it at Lowes near the other penetrants and such. The can is huge (12 oz.), has a green lid, and cost about $6.00. The label doesn't say it is silicone based, but it is. (The junk smells like a bag of used condoms!...Takes me back to college...lol) Make sure and wash it off your hands!! It does say that it is biodegradable, but also toxic.
I've tested it on all sorts of plastic and rubber without any damage. It has excellent lubrication properties and works just like regular airsoft silicone spray except it seems to be a bit more viscous, which wasn't a problem. I have used it to clean and lubricate my AEG and GBB after several skirmishes without any complication. I have also used it to lube up and repair a plastic AK magazine that was all boogered up and had a seized internal spring from using petro-based lubricants in it before i knew they sucked. This demonstrates LubriMagic's ability to lubricate plastic without damage. It didn't hurt my hopup, and it is cheap. Thus, I am impressed enough to suggest that others try it out.