Microsoft SQL Server family includes free Express edition, that is fully functional, however has some disappointing limitations which prevent from using it in development process. One of them is absense of profiling tools, standard SQL profiler is not included.
I found the this Free Tool "SQL Server 2005 Express Profiler" which is pretty good. SQL Server Express Edition Profiler provides the most of functionality standard profiler does, such as choosing events to profile, setting filters, etc.
Download it for free from http://code.google.com/p/sqlexpressprofiler/downloads/list.
This is open source project, it is absolutely free and can be used as is.
