Cheap tweak from Virtual Dynamics:

Might as well make sure the screws stay torqued too.
http://www.threadlockers.com/vibratite.jsp

I torque screws on my spring guns (pellet guns), and use vibratite to ensure they stay put. One of the nice features of Vibratite as a thread locker is that the screw can be removed and inserted several times before it needs retreated.

The Vibratite is the missing link, I think. I have always wanted to tighten my drivers' screws, but I always thought I would just keep having to do it, and that they would eventually strip. Great solution!

I'll probably dig out my Utica 6 -30 inlb screwdriver, and try this tweak. My Gemme Audio Tanto speakers do not have grills, and the fronts are black, so the fun part will be blackening the brass screws.

http://www.modelboatyard.com/blackening.html

I would be very careful if you plan to monkey around with your loudspeakers' driver mounting screws. Most higher end speaker manufacturers understand the importance of mounting screws, especially with regards to equal torque and loosening over time. As such, the better manufacturers torque them correctly at the time of assembly and may even add a little thread lock to keep them from loosening away from their original torque.

Some food for thought:
Regarding the higher end loudspeakers, just as strong an argument can be made for leaving well enough alone. Once the screws have been "seated" at the time of assembly, it may not be a good idea to break the screws away from their seated position. The integrity of the screw hole may suffer and you may end up with a connection that always needs adjustment from that point on.

Amen Seasoned.For every 20 happy campers,there's going to 1 who wished he never heard of the word Torque.Those wrenches mentioned will be accurate 1/2 the time if that.But what the hey,boys will be boys.Along those lines,I will ask said people who are tweaking "Where is the most accurate reading on a torque wrench"?Cheers,Bob