TourneyLogic bracket control is a godsend
I've had the sample Tourney Bracket Control from TourneyLogic for a few weeks now, and I just got around to playing with the API directly in preparation for an online contest my station is doing for the upcoming NCAA March Madness basketball tournament.
Because of budgetary constraints (my own), I decided not to buy their automatic Tourney Poll Manager, which is also really sweet, and build a back-end myself for the database structure and reporting front-end stuff.
It was created in ASP.NET 1.1, and despite some lengthy development time (I have yet to setup even small tourneys fairly quickly), it's amazing. I'm also scheduled to have Joel Ross and Brian Anderson on my radio show in the next couple of weeks to talk about college hoops and life in Michigan.
Even if you're not into sports or plan to do those types of apps, download the free samples and give it a whirl. It's very impressive.