ASP.NET Timer control
I've uploaded my ASP.NET Timer control to GotDotNet User Samples today. Here's the blurb about what it is and why you might need it:
Provides a mechanism for generating recurring events at specified intervals. This can be useful if you have something like a hidden frame that needs to be refreshed at specific intervals or a hidden frame that is used to poll a server.
I probably should've called it ServerPoll or something like that. One of the neat features of this control is that it also exposes on the client to notify about it's current state.