I will be sowing cauliflower & calabrese in October which I overwinter in the coldframe plant out March (hopefully) and get a lovely harvest very early before all those nasty cabbage whites get going! I also sow peas and mangetout in guttering for the coldframe and plant out as early as weather permits.
I sow winter lettuce (under cloches)using a good selection and harvest as cut and come again throughout winter, then early spring leave to grow on to normal size lettuce, this has worked well for me the last two years.
Its also a good time to sow your own onions for overwintering, seed sown onions always do better for me than sets.
I aways sow my broad beans in October, I am prepared to give them a little protection against the wind, but the advantage for me is they stand up well against the black fly.
I do try to make the Lotti earn its keep all year round so my winter goodies will include parsnips,leeks,sprouts,psb,spinach,chard,salad leaves, I do find my cabbage seems to sit and sulk until spring then does really well.
Good luck with whatever you choose :)