Is there any easy way to identify the type of bearing used in a fan?
Usually it will be listed in the specifications, either on the web site of the retailer or on the manufacturer's web site. If the type of bearing isn't specified it is probably sleeve; pretty much any *other* type of bearing -- ball or any of the FDB variants like S-FDB, hydro-wave, etc. -- is a desirable feature, so sellers tend to mention it.
I have also come across a maglev type and wonder how good they might be... one would assume minimal wear and tear.
There was a lot of hype about that tech a few years ago; I forget the name of the company that was making them. IIRC the first production run suffered from some sort of quality issue (motor tended to overheat or something...?), and I haven't heard anything about them since. Anyone know if they're still around?Edit
: On second thought, it is possible that I am actually thinking of "tip driven" fans, where the motor is in the perimeter of the housing (and drives the tips of the blades), instead of in the hub...
If the world isn't making sense to you, you're either drinking too much or not drinking enough.