Your normal sleeping time is 8 hours. Still you can use an item's ability which is stated as once/day after every rest (i.e. max 3 times a day) but can't use it again if you travel for more than 24 hours.
Stoneskins however (duration 12 hours) wear off while sleeping for 8 hours (they don't do if you travel).
Also spells like Remove Fear (duration 1 hour) seem to last shorter (I KNOW it's game time).

<font color = lightgreen>Quite fun, isn't it? [img]graemlins/1dizzy.gif[/img] The game seems to tie sleeping together with 1) item recharge and 2) clearing active spells.</font>

Faceman,

That's not quite true. I often cast Stoneskin / Ironskin directly before sleeping, and I have four hours worth left when I wake up. It's one of my favorite pre-big-fight tactics, especailly good when one's too low-level to have 2 5th level Druid spells... sleep, cast Ironskins, delete Ironskins, memorize Insect Plague, sleep, go fight.

-- Nifft

I've never been able to keep my stonskins! I would have really liked to.
I always do the job with contingency (Stoneskin on sight).
Cast contingency - sleep and memorize something else - Fight with stoneskin on sight.