So I have a really nice plastic shelf I could be building my rigs into but I'm worried about static discharge. I would assume if the psu is making contact then the shelf would be grounded but wtf do I know about static electricity... am I being paranoid?
Yeah kinda..lol

Don't worry much about PSU grounding, most of the PSU has already a grounding from the power cable wall, some peepz are worried with platic racks due to fire hazards, however its your choice if you would ask me, I do prefer plastic over metal racks as I am much worried on short circuits

What I meant about the psu grounding through contact is in a conventional computer the case, as well as the mobo, are grounded through contact with the psu but I don't know if that would be the same affect with a plastic shelf.