This little lump is one of my best hobby tools. It is a lump of clean clay. I use it to hold paint brushes when I am painting. Rather than lay it on the table, I stick the end in the clay to hold it upright. I also use the clay to prop up parts while they are drying. Finally, clay can sacrifice itself by ending up in the nose of tricycle landing gear airplanes. It makes a great weight to keep aircraft in place on their gear. I often include small shot gun lead pellets in with the clay. The clay keeps them from rolling around inside the model.
Florist pliers are great for light wire cutting, and plastic cutting. They also make good light pliers. I got them at Michael's craft shop and paid about a dollar for them.
Canned dust remover. When clean up time comes it's nice to be able to get the nooks and crannies of the model by using canned air.