I've wondered for awhile why there are no Bluetooth Flash Drives (or at least why I can't seem to find them). There are dual-purpose USB flash drives / USB Bluetooth dongles, but no drive that I can connect to over Bluetooth.
It seems this would really solve the problem of synchronization I discussed in the past. The USB flash drive idea works well in theory, but I found that it was not sustainable in practice. When I had a thought, I wanted to be able to capture it immediately. As ridiculous as this may sound, the extra step of taking the drive out of my bag and plugging it in to do this just didn't work; often I found myself just resorting to local notes instead.
If it was always connected, however, I wouldn't have this problem. The only thing I would need to do is make sure I had my flash drive, something I could easily do. (Analagous, perhaps, to remembering to bring a physical notebook).
Actually, I've been thinking of using my smartphone for precisely this, but I haven't yet figured out how to map a drive letter to the storage card.
It seems that the Wireless USB protocol is being finalized, and it's hopefully a Wireless USB Flash Drive is among the many products to be released in the coming year.
Engadget cites ease of configuration (or lack thereof) among the reasons why Bluetooth hasn't quite caught on. There are certainly heard horror stories with Bluetooth compatibility, and although I haven't run into any problems myself, USB devices are undoubtedly easier to use.
In the quest to make Wireless USB easy to use, I only hope they don't completely ignore security. (A WEP-like system, although not perfect, would be a start). In the case of a wireless drive, maybe it's better to err on the side of caution (in terms of granting access) than just making it easy to connect.