Well, I think it depends on what kind of stuff you want to build and what your budget is. Here are a few ideas that come to mind:
Furniture
- Bed lofts
- Desks
- Shelves
- Massage Chair (man that'd be a fun one)
Appliances / Electronics
- Robotic vacuum cleaner?

Tytus instead of Roomba. Sounds catchy
- Compute
I'll add more as I think of them...