Free ASP.NET Controls
Matt Hawley has a terrific set of custom controls on his Excentrics World website. How did I miss these for so long? In addition to a few standards (calendar, show/hide panel), he's added some highly practical variations like a textbox that uses an input mask (see the phone number demo) and a time picker to go with all your calendars. Nifty.
Matt's blog is pretty cool too. Looks like he does a fair number of reviews and has a usable rating system (as in he actually scores components a 1 from time to time rather than alternating between 4's and 5's).
Anytime the topic of controls comes up, t'would be remiss to omit Andy Smith's terrific MetaBuilders site with a mix of indispensible free and commercial controls. Andy's just released the MultiViewBar, check it out! [Andy's Weblog]