BT will make a small charge for caller ID. Presumably you would want to use this in conjunction with Call Waiting (another charge) to decide whether to take the call? The call waiting beep may cause your internet connection to drop, though.
the modem I use offers caller id as part of software package called Webphone .Supervoice.Try looking at the driver cd under explorer and read each Txt file or pdf (adobe acrobat) I dont actually use my modem for anything but surfing.
Dream on, most if not all modems are not true UK. Caller ID wont work as it's USA style that comes after the first ring whereas BT send it before the first ring. Pace & Psion, both now defunct made UK modems that worked with caller ID. Symantec have a free download to give Caller ID check the site. It's very annoying that all these Magazines fail to complain of this continuing fault of modem suppliers, yes I have complained to both without effect.