It does to a point -- there is no interface for it however. You can use the "net send"
command to send these types of messages (receivable to WinPopUp and vice-versa). To do so,
click the Start button, then click
Run, and enter:
net send computername themessage
Where the computername is the computer name of the person you're sending to, and themessage
is the message you want to send.
I use WinMessenger - much better than WinPopup ever was. Works with
all W9x, W2K and XP. It has very nice, "native" user interface under
Windows XP and drop-down list with users...
Really nice tools and I'm strongly reccomend you to try it. It can be
downloaded from http://www.winpopup.com