I found a recipe for sauerbraten in the slow-cooker cookbook. I use recipes for entertainment sometimes. This is one of those times. I had no idea what it would taste like, but it called for a beef rump roast, water, vinegar, lemon (sliced), cloves, onion, 4 bay leaves, 6 peppercorns, 2 T salt, and 2 T sugar marinaded for 24-36 hours. Then put in the slow cooker for 6 to 8 hours (I left it in for eight hours). Then it said to remove the meat, turn the crockpot to high and put in 12 gingersnaps pulverized. Leave it on high for 10-14 minutes.
That sounded so interesting, I had to try it. Thickening the sauce with gingersnaps instead of flour almost made the whole thing worthwhile. While it thickened, I sliced the meat and put it in the sauce. Then I made cauliflower "mashed potatoes" to put the meat and sauce on. It was different, but pretty good.