From Popular Photography Magazine :
"11) Mr. Softee.If your portrait subject needs softening, but you don't have a soft-focus filter, the pro who goes by the name Wolf189 (http://www.wolf189.com/) suggests trying a slower shutter speed. Shooting with a continuous light source at 1/15 or 1/8 sec (on a tripod!) will usually soften wrinkles and other complexion problems just from the movement of your subject breathing. "
The complete list of tips and article: