When Anikin and Qui Gon return from meeting with Watto after the pod race, Shmi is sitting at that tabe working on a gadget that looks like a circuit board of something.
According to the EU she was employed by Watto to clear and repair alectrical equipment, circuit boards and the that sort of thing.
If you look at the tools on the table, you can see a lot of items that might be applied to a job like that.