Thanks, this is all useful... a few remarks inline...

On one level, you're preaching to the converted - my servers are FreeBSD, my desktop is Debian, my router is DD-WRT and I didn't buy a Linux phone by accident. :-)

That said, I can pay for one contract SIM at a time, so the N900 is most definitely a phone - in fact, it is now my only phone, being the only GSM terminal I carry and also the SIP phone that fields all my landline calls when at home. So, as much as I appreciate the tablet functionality, I need it to work well as a phone, whether out and about, or at home. I'm not griping, just thinking it's time I spent the money on meeting those requirements as best possible.

Regarding the BH-905i, there are at least a couple of reports on here that they are compatible and work better than the 905 - what I'm finding harder to decide is whether they are what I want, and that's rather subjective. I'm not a regular user of Bluetooth headsets and don't really know what my criteria are, just fishing for any experiences of them. It's between those or the full-blown over-the-ear Sennheiser MM-550, and I'm as interested in call quality / convenience / practicality as music listening.

As for the memory card, all noted and agreed, I'm likely to go via Amazon, play.com or one of the usual suspects, probably for the Lexar judging by the existing reviews.