I do with them absolutely nothing...

...though once upon a time, I had an idea to use such a card in a troll build, as the only connection 🤣

I use them for (de)soldering practice. 😁 Well, at least the broken ones.

One or two of my old PCI 56k modems might still be functional, but I have no use for them nowadays. I hated those flimsy things with a passion back in the day, and had them packed away the second I got faster internet.

I don't think I ever personally had a PCI modem. Other than one integrated in a notebook. I had external and ISA modems though.

At work I still have a FAX modem in use in a Laserjet all in one. They still come integrated in various printers. They can have problems with modern internet based phone lines though. I had to disable its error checking and v.34 speeds.

I ran out of expansion slot covers, so I put a modem in that slot to fill the hole in the back of the case. I think it still works (since Windows detected it and installed the drivers), but I haven't had a use for it.

you bridge dreamcasts with them

I think I heard or read that some of these cards could potentially be used by Asterisk, so one could built their own PABX - and hence have something that old phones and modems could connect to - but I'm not sure if I ever found any information about what cards are supported, if any.

lti wrote on 2023-04-22, 21:00:

I ran out of expansion slot covers, so I put a modem in that slot to fill the hole in the back of the case. I think it still works (since Windows detected it and installed the drivers), but I haven't had a use for it.

Not enough slot covers is always a problem! You could probably unscrew the bracket from the card and just use the bracket 😁

I never used any modem cards in any of my builds, though I did consider it especially for the odd AMR/CNR/ACR slotted ones (not sure I even have any boards for all of these slots). But the main issue for me is how useless the are. The dialup tone would be kinda nice to hear again I guess.