We have all heard the admonitions to dispose of remaining brake fluid once
we are done with the open can, but check out this recent post on
alt.autos.gm:

<quote>
Picked up a bottle of brake fluid off a shelf in the gargage yesterday
and heard a funny noise. There were three little balls of ice floating
around in there.

Never seen that before.

This was left over fluid from September 2004 when I changed front brake
hoses on the Bonneville.
</quote>