Yep, I do something similar. You can get a two-pack of 3 gallon fermenters and do half batches. I like to brew a 5-gal batch and split it across two three-gal fermenters. One might get American Wheat yeast, one might get hefeweizen yeast. Or both might get hefeweizen yeast and one ferements at 65 and the other ferments at 58. Or one might get dry hops, the other doesn't. One gets raspberries, the other doesn't. Possiblities are endless.