Unfortunately, this is now no longer quite so easy because you only have any no-name and cheap products gets in the known electrical markets (although not reflected in the price). Downside to these products is that no longer adheres to the standard, and thus may lead to problems under Linux.
These D-Link, however, that's not an issue, just plug in and work!
Optical (the image is right the time not, he's black piano finish and relatively flat) it is not bad either and thus a clear recommendation (not only for the Raspberry PI)!
