imeem is a supercharged instant messaging service that lets you share personal media & stay connected with friends.
imeem for windows requirements:
Windows XP (Home and Professional), Windows 2000 Service Pack 3 or greater, or Windows 2003,
Internet Explorer 5.5 or greater.
Microsoft .NET Framework 1.1 or greater.
imeem for mac requirements:
Mac OS X 10.4 (Tiger)