Paint agitation

Someone suggested putting marbles/ball bearings into paint. 

Questions: 

1) Paint tends to settle in large clots in the bottom of the glass jar.
How much use is a marble frozen into this guck? (My point is you require
a fairly viscous situation even to gain the benefits)

2) Is there a risk of reaction with the paint from either type of
foreign object? 

3) Does the inestimatble Mr. Bell realize how he made me smile? The
image of him putting some sort of paddle into his paint on the tip of a
5000 rpm Dremel (low setting for most of them) was rather hilarious...
and would probably be very messy, unless he was lucky enough to own one
of the older 295's with a foot pedal. 

I will try some marbles or small ball bearings, but I guess one want
stainless ballbearings? 

Tomb

PS - anyone have an idea where I can get good (as in normal size but
with a great lid) EMPTY paint jars? I love the Armory paint jars I got
from some of their discontinued lines, but I need some more containers
to store mixed paints/washes/etc. 

PPS - Allan talking about crashing a VTOL onto the guy who shot it down
ought to be familiar to the Kra'Vak from Grey Day To Die.... several
Kra'Vak Aerospace fighters went down and at least one went down right on
top of another unit....