Swimming is an option, row boat, canoe, inflatables are others. I have a fishing pole with a tennis ball tied to the end that I can throw out and usually drop a line over the boat and reel it in. I also use a PWC and a 1:1 boat for retrival when I'm on the big lake.

Boats are a lot of fun to play with too. I particularly enjoy the tunnell hull style with an outboard engine but some of the mono hulls are cool too. They can be very fast too. There is video of an outrigger style boat being radared at over 119mph. There are lots and lots of kits to build boats. You can even get just plans and buy all of your materials and build one from scratch. They can also get to be quite large. I've seen rc boats that are 7 & 8 feet long.

I've always enjoyed building kits but it seems like, at least in MT's, the industry is trying to satisfy our general lazieness. The I want it and I want it now syndrome. On the brighter side, the more people that are in the hobby, the more vehicles they will sell. Hopefully a higher sales volume will translate to lower prices.
Well, we can hope right???