LINQPad is a modern SQL query tool. Say goodbye to the old SQL Management Studio. LINQPad supports SQL Express, SQL 2008, SQL 2005, SQL 2000, SQLite, MySQL and Oracle.

LINQPad standard edition is free and can run without installation. The executable is 3MB and is self-updating. There is even a version that runs in Google Chrome.

Autocompletion is an optional extra. You can buy LINQPad Pro for $39.00 or LINQPad Premium for $58.00 (introductory price). The Premium Edition also unlocks LINQPad’s ability to write cross-database queries. Just control+drag additional databases from the Schema Explorer onto your query.

Here is the official LINQPad website: http://www.linqpad.net

Here is an example screenshot: