One more GUI app in the SQL space, Aqua Data Studio:
Aqua Data Studio is a SQL editor and developer tool that allows developers to easily create, edit, and execute SQL scripts, as well as browse database structures.
It’s Java based. I gave it a try, and it does have a number of nice features, but it seems to want to get all the results from a query before returning anything, which made it difficult to use SELECT * FROM FOO on large tables to quickly get a peek at the data…