I do, and here's how I do it. I take the old potting soil, put it in a 3 gallon pot, and pour a kettle of boiling water through to kill it, then I mix it half and half with new potting soil. Things grow very well in this, and I've never had any root rot problems from the old soil.
Didymo (Didymosphenia geminata), also known as rock snot, is a non-native invasive microscopic algae (diatom) that can produce large amounts of stalk material to form thick brown mats on stream bottoms.
The Didgeridoo. The aboriginal didgeridoo (didjeridu, dijeridu, yidaki) is a long, wooden wind instrument or horn used traditionally by the aboriginal people of Northern Australia. Rock paintings on caves have established that the didgeridoo has been used as a musical instrument for at least 20,000 years. It is made from a tree branch, usually eucalyptus, hollowed out by termites. Branches cut into varying lengths produce instruments with different pitches.