Here's some Bally's Safejack 101 and Dave's right, you don't see 'em as much these days. I got my first one in Jan. '00 from Mike Spinetti on eBay. Mike doesn't sell much on eBay now but when you'd get your winner from Mike, it would be mummified in various wrappings of USPS Priority tape, Kevlar and carbonite. Mike had this to say in his auction presentation:

Mikohn SAFEJACK Casino Chip used at BALLY'S L.V.
"The big chip with a little chip inside" - a computer chip that is! Used on only three tables in 1996 at Las Vegas' Bally's as an experiment (beta test), the table was rigged with lights and a shoe that registered the card as it came out of the shoe. Your chips were counted and your bet recorded. And a red light came on telling you, you had just busted, even before the card out of the shoe got fipped over. Because the chips were expensive, you couldn't walk with the chips but had to cash them in at the table for regular house chips. But as I pointed out the flying pigeon overhead to everyone at the table, I pocketed one $5 chip for me and an extra for you.
P.S. Big Brother Blackjack was a flop, and the game removed.

Don Lueders made a very interesting post about the system here: http://www.thechipboard.com/cgi-bin/bbs521/tcbarc04.pl/read/121184

Two variations of the chip as seen here. TCR# N9283 large square on the left and N7968 small square on the right. that's small and large red square BTW. Another curiousity, the chips were made by B et G...first ones in NV.?