Electronic equipment, too-always strip a piece of electronics, before you might throw it out. Radios, computers, lamps, stereos and speakers-all contain fine-gauge wire and bits of metal and plastic.
And resin casting blocks, from any resin pieces that come with any kit you build. If you don't just sand the pour stub down, but cut it off, throw it into a jar.
Did we mention to save jars, too? I use plastic peanut butter jars for storage, and not just on my modeling workbench, but also on my big workbench in the garage. I use them to sort and store fasteners (nails, screws, nuts and bolts), and all kinds of odds and ends. On the modeling bench, they hold my groundscaping materials (Celluclay mix, baking soda, used tea leaves), small bits of sprue, spare parts.
Save little jelly or mustard jars, too, like the ones that come in gift boxes. I use the glass jars for mixing paints, holding small amounts of solvents or spirits for cleaning brushes, etc.
The upshot-we're packrats.
Regards,
Brad