There are still a lot of routers and RAS servers and the like the "require" telnet if you want to get in to them remotely (ie. to admin them). Yeah... pretty much means that you get to setup a "secure" segment/vlan that only runs that sort of stuff if you want to try to make it unsnoopable (or put an ssh server in front of it with a small private net, etc).

But telnet has other uses other than just "login" -- I'll refrain for further "useful information" in this forum, however.