Todd is collecting a lot of fine sawdust from renovation work and doesn't want to throw it away. What do to with it?
First on the safety side of the question. Fine sawdust in the air is explosive! Keep it in closed containers. Sawdust with any volitle solvents in it is like cleaning rags, it can create spontanious combustion, so don?t use it to soak up solvents.
It can always be used as a sweeping compound, such as to soak up oil spills, or if slightly moist to pick up floor dust. But large scale uses are a bit more difficult to find.
You may think about using it in the garder, but be conservative because sawdust draws nitrogen out of the soil, so you will have to add slow release nitrogen for 3 to 4 years after you have used it as mulch. You can use a bit in compost, but only a thin layer after a layer of wet material.
Sawdust is recycled in industry to make pellets for wood heating stoves, to make particle and press board, and even mixed with plastic soda bottles to make deck and boardwalk lumber called Trex.
Some lumber yards will accept clean sawdust for recycling and you can check with your local recycling centres for other ways to dispose of quantities of sawdust.
You may want to check out a recycling/waste management resource for North America called Earth's 911 -- www.1800CleanUp.org. It will give you all kinds of specific information for your local area, plus lots of good general information.