Originally Posted by
Plow13
I also remember a lock that was somehow incorporated into the waterbottle cage. Anyone ever seen that before?
Is this what you mean? The Abus Bordo "Lite" versions come in at 650g weight (albeit at a cost in security). The heaviest ones are ~1.5kg. The tipical model expands to form an 85cm enclosure.
They come with a casing that can be mounted instead of the bottle holder, or you can stick the lock into an actual bottle holder if you find one that fits.