So I found a job.
Just to recap my life since December:
I had worked with Bytemark for seven years and left for reasons which made sense. I started working for "big corp" with a job that on-paper sounded good, but ultimately turned out to be a poor fit for my tastes.
I spent a month trying to decide "Is this bad, or is this just not what I'm used to?", because I was aware that there would obviously be big differences as well as little ones.
At the point I realized some of the niggles could be fixed but most couldn't then I resigned, rather than prolong the initial probationary training period - because I knew I wouldn't stay, and it seemed unfair and misleading to stay for the full duration of the probationary period knowing full well I'd leave the moment it concluded - and the notice period switched from seven days to one month.
A couple of people were kind enough to get in touch and discuss potential offers, both locally, remotely in the UK, and from abroad (the latter surprised me, but pleased me too).
I spent a couple of days "contracting", by which I really mean doing a few favours for friends, some of whom paid me in Amazon vouchers, and some of whom paid me in beer.
e.g. I tweaked the upcoming death Knight site to handle 3000 simultaneous HTTP connections, then I upgraded some servers from Squeeze to Wheezy for some other folk.
That aside I've largely been idle for about 10 days and have now picked the company to work for - so I'm going to be a contractor with a day-rate for an American firm for the next couple of months. If that goes well then I'll become a full-time employee, hopefully.