Received the following question: Please feel free to add your comments to my own.
Jim
What are the recommended (or even required) add-ons for the NXT set? I just bought the set, but also felt the need to buy a couple of Technic sets so that I can big builder bots/etc.
Jim's Answer: As of right now, there are no "REQUIRED" add-ons... there aren't even any NXT expansion sets yet. The NXT is still considered quite new. There are a variety of 3rd party sensors now available from Mindsensors.com and HiTechnic has partnered with LEGO to sell their sensors (see an earlier post on the Compass sensor I tested). I'll let readers make suggestions for other sets that you might like...