Canon T90 Vertical Grip
Built using a modified VG10
(normally for an EOS5), the T90 was modified to have 3 contacts at the
bottom of the grip (gold contacts from an old ISA PC-Card, wired to the
cable release socket) that match 3 spring contacts on the grip. Allows
to hold, meter and release in vertical position - and most important
prevents the T90 from falling on it's nose with a lens attached :-)