In reply to mick taylor:
Don't bother pricking the sloes. It makes no consistently perceptible difference if you leave it for long enough - at least to my tastes. Just invert the jars for a few minutes once a week or so for the first 3 months.
As for the blackberry vodka, when you filter it, mash the blackberries up and put them in a chocolate truffle mix (melted butter, milk chocolate and double cream, simmered on a hob. Google for sensible ratios), then refrigerate the mix, then ball the mix up into truffles (after keeping your hands in iced water as long as you can bear), roll them in cocoa and re-refirgerate. Once they're cold, dip them briefly in molten 85% cocoa chocolate to coat them and re-re-refrigerate. Perfect blackberry vodka chocolate truffles. I take hygiene up several notches when making these compared to most foods.