Is there a simple way to detect open database connections? Right now I'm putting Debug.Writelines in my I/O routines to determine whether I'm leaving connections open and it's just not an efficient way to find this problem.

FYI, I have not found any such tools. However, I was able to create a tool that opens multiple browser windows. If MAXIMUM POOL SIZE is set low enough in the connection string, an error can be induced by opening a sufficient number of browser windows. This is the only mechanism I've found for detecting this sort of error. If anybody is interested I will happily provide a copy of the source code for this tool.