Of course, I'm really looking forward to our (possible) vacation in the Black Hills. It's our opportunity to do the whole tourist thing, and we plan to take full advantage of it.
I think we'll be doing Wall Drug, the Lewis & Clark Keelboat Center, Mt. Rushmore & Crazy Horse memorials (of course), the various wildlife/scenic routes in the Badlands/Custer areas, Jewel Cave, Deadwood, the mines at Lead, and *maybe* the chuckwagon dinner and show at Circle B Ranch (argh, looks like it may close for the season the week before we get there) and/or the Reptile Gardens. But the thing I'm most looking forward to (other than the scenery), is the Mammoth Site. Yes, in spite of age and theoretical maturity, I still completely geek out at the idea of digging up old bones (and old buildings, and old pottery... anything historical, actually. Nowadays that pretty much means anything that pre-dates me).
Let me know if there's anything else you've done in South Dakota (or on the road between Minnesota and SD) that really made you squee. Restaurants, good motel deals, roadside attractions that may not be on the normal tourist agenda, we're up for it if it sounds interesting.