I have started to collect Newtons (to go with my original Messagepad that I paid $700 for) and have a couple of questions. On which Newtons can you use the Newton keyboard? Is is just for the Messagepad 2000 and 2100? Are clear Newton 110s really that rare? There have been two for sale on eBay in the last month (going for $510 and $460). Does anyone have an idea of how many were made?