If you haven't worked it out by now, I am using my blog to capture useful titbits on SharePoint, BizTalk and InfoPath that I don't want to forget myself.
Anyway - here's another useful one for SharePoint and Data View web parts that I think is great, but maybe just not that obvious for working out yourself.
The idea is to effectively create a simple "search" facility on a Data View web part, which is enabled by creating a Form Web Part with a single text field that provides this value as input to the Data View, the Data View is filtered based on the input value.
One gotcha I came across was trying to setup a Contains filter on a Lookup column. It seems that it is a constraint imposed by FrontPage 2003. I found that you can set it on a string value, have a look at the XSLT, and then apply this same change to a Lookup column and it works fine.