I'd like to be able to use IM with my wife at work - she can't install anything on her computer but does have internet/email access. Does AOL, MSN, Yahoo, etc offer a way for her to use IM via a website (vs the installed software) and communicate with me at home using iChat, MSN, whatever? She's using a PC at work and I'm on a Mac at home, if that makes a difference.
Any help will be greatly appreciated!