Its really great that we have major antivirus vendors like Symantec (Norton) and McAfee and Trend Micro watching our backs (and making a good living at it) with virus software and signature file updates. But the really cool work IMPO (in my professional opinion) comes from the likes of Kaspersky, Panda, and Eset. These guys continue to come up with creative methods for detecting attacks and then cleaning them. And then there's AVG whose "free" simple tools serve as a fantastic marketing platform to sell their more sophisticated products.
The down side of "creative" approaches is that the user - of the browser-based detection method - has no way of knowing whether the test is reliable and valid and that the vendor is authentic.
So beware of anything that purports to be a test or wait for one of us (the security pros) to comment about it, give you a reliable heads up to authenticate the author, and a means for identifying the real thing.
And I haven't tried Gauss detection yet. When I have time - and courage I'll test it for you.
Online detection of Gauss - Securelist