>How much more - will it run ok on a laptop with 512Mb RAM? Is this SSE itself taking up the resources, or the .NET framework it sits on top of?

It's SQL Server. I don't remember the exact numbers now but SQL Express seems to run close to 100 megs when in use. Full SQL Server runs even heavier even in minimal configuration on my machine, but then that might be because my system has 2 gig and it might be relative to available memory.

>The main reason for going with SSE is that I am about to dive into learning ASP.NET using Visual Web Developer Express as a design tool, and from what I can see most of the data-access examples that come with the VWDE tutorials use SSE. However, if SSE itself has a large footprint, can ASP.NET just as easily use another database (eg. MySQL) using ODBC connections?

Youc an use other databases, but all the samples will be SQL databases and you'd have to convert them. So not a good idea for training.

512 megs should be enough...