From the MAME Forums:
"Years ago we had a forum member named oNyX who used to go around to arcade auctions and California Extreme type events and take pictures of cabs for MAME use. He also collected pictures and info from ebay auctions around the time (2000-2003ish). It became several gigabytes and was shared through a couple of FTPs for certain groups. Eventually most of it went up on a MAMEfans website but not in a way where you could just download it all. I've tossed a few other things in there over the years like the old fan videos and magazine scans talking about MAME. There are pictures that could be added to various packs or used to improve some of them. In fact this collection was what I used to start the original cpanel packs way back when. Anyway, they need to be backed up on more hard drives so if you feel like it, here you go. There are cabinets from our era and also antiques, pins, weird stuff.. you name it."