I have a couple of Fore Systems ForeRunner PCI interface cards for 155Mbps ATM. Those remain supported by Linux mainline, at least in theory the driver is still around. Not sure if anyone used it in the last 15 years, so there may be bugs.
Is anyone running some ATM technology for fun? I only have high-level theoretical background about ATM. I'm wondering if ATM cards can be connected back-to-back or if I'd need a concentrator or the like?