Worth noting:
This test checks which CSS3 features the browser recognizes, not whether they are implemented correctly.
SQL Fiddle
Think of jsFiddle, but then for databases: Create schemas and run queries on them. Microsoft SQL, MySQL, Oracle, and PostgreSQL supported.
Ringmark – Acid test for Mobile Browsers
Ringmark is a web-based test suite that measures how well a mobile browser supports the capabilities that modern mobile web apps require.
Roughly translated: “Acid test for Mobile Browsers”
(via Jeremy)