This list is updated as of MAME 0.197 and DAPHNE 1.0.12. Daphne is an emulator written by Matt Ownby which lets you play LaserDisc arcade games, like Dragons Lair, Badlands, Cobra Command, Space Ace to mention but a few.
This will hopefully be fixed in the future thanks to the Domesday86 project which employs a combination of specialized hardware and open-source software to preserve the discs in a far more faithful manner than ever before. Then again Ive got a real Dragons Lair and a Mach 3 here. The reason MAME doesn't emulate many LaserDisc-based systems, is largely due to indecisions regarding the disc preservation method and format. Daphne is cool stuff, but yeah you need the original laserdiscs (from eBay).
Use DaphneLoader to update DAPHNE and auto download games.