Here at TAIsoftware we use

VS.Net 2003    (of course)
MSDN           (Ditto)
VS 6 (for some older vb apps we support)

Databases
SQLServer 7 and 2000
Postgres
Oracle
Cache'
DB2
MYSQL

I was tired of using different tools for each of these DB engines so we wrote a tool that supports most of what these engines can do via ODBC connections and mimics the interface of the SQLServer client tools for SQLServer 2000.

We also wrote our own GRID control that is in most every thing we write for our customers in one form or another.

We have also written our own Graphing Controls, and data visualization controls for simillar purposes.

We tend to craft what we need for things because part of our process leaves our clients with the source for their applications. As we do a good job they don't usually have a need for anyone else but if they did they would not be left in the lurch with the binaries for an application that they could not fix a problem with. By being fairly plain jane our clients can replicate the env that their products were developed in without alot of expense and configuration know-how.