Seeing someone else's post on foam problems reminded me.
Years ago I had 3 A4 size sheets of black conductive foam covered with ICs
and for storage placed one each in a new manilla envelope with
details written-up on them. Stored with open flaps, vertically
in a drawer of a filing cabinet indoors, not in a shed. A few years later
came to
use one and all the pins on all the ICs were affected by rust
to the point that some were rusted away totally.
Gummed flaps on envelopes were fine unstuck and no other traces of damp.
Anyone else experience of this?

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/