SQL 2005 Service Manager
http://www.sqldbatips.com/showarticle.asp?ID=46 With SQL 2000, they had this nifty little tool that sits in your taskbar that allows you to start/restore all of the different services that are associated with SQL server. They took away that tool with SQL 2005. This tool works for SQL 2005-2012 and is great to have in a development environment where you would like to restart services.
ExpressMaintUtility
http://www.sqldbatips.com/showarticle.asp?ID=29 Another tool that I use from them a lot when I have to set up backup jobs when the server is running SQL 2008R2 Express which doesn't include a service agent to schedule jobs
BIDocumenter
www.pragmaticworks.com When I have to look at a database that is new to me, this is a great way of spitting out the entire schema of a database and put it on a chm file.
CloverETL Designer
www.clovertl.com I still use SSIS but this has some nice features that I have used.
SQL Spy
www.hybridx.com I have to take care of a LOT of SQL servers. This free tool allows me to montior multiple servers at once. I still use Utility Explorer for my main servers which comes along with SQL 2008R2/2012 Developers edition
SSMSBoost
http://www.ssmsboost.com/ A great addin for SSMS that adds some nice features. It uses the Poor Man's T-SQL Formatter which is the only tool that I have been able to find that works and doesn't crash my system when jumping from server to server
QURE Analyzer
http://www.dbsophic.com/ A different tool for analyzing trace files. I think it does a better job than SQL trace and DTA
Spawner http://sourceforge.net/projects/spawner/ This is a great tool for generating data for testing purposes. To be honest, I used it more when I was teaching since I have too much data now but still a great tool. I haven't been able to find anything else out there like this without spending a LOT of money