You know, when I transfer to secondary or to a bottling bucket, I just swirl the bottom of the primary a little and pour about 4 cups of the slurry into a sterilized quart mason jar and stick it in the fridge. The night before I brew I set it out on the counter to warm up and the next day I crack it open and pitch it right in the new wort. Not the most sanitary method on the planet but hey.. It saves me $7 and I've never once had any cross contamination or batches spoil because of it. I keep the standard stuff at the ready at all times, american and english ale, saison, hefe, belgian strong, lager and a few more staples taking up the entire middle shelf of the fridge. The wife LOVES that.