I've been meaning to join this for a couple of years, but held off till I was more confident about my seed saving skills. For your membership, you get a few seeds of each of six rare varieties; I also got some Hughes Huge peas as a new member. By sheer coincidence, this was one I already fancied, as I like tall peas, which crop more heavily, and it's ever so easy to save pea seed. If you volunteer as a Seed guardian - I have - you get a list of 'orphans' in March, and choose up to three. You grow them and return seed to HSL for distribution. So I should get eleven varieties (with a lucky dip bonus variety) for my £20, which isn't bad going.
They distribute a catalogue containing about 200 varieties to pick from. the emphasis is on peas, French beans and tomatoes; these are all self pollinated, and really easy for seed saving. I haven't yet experimented with saving seed from cross-pollinated species, but I'm going to have a try. The trick is to stop them crossing with other varieties grown nearby.
Meanwhile, however cold it is, the days are lengthening noticeably, and the first snowdrops are blooming. Spring is at hand!