The starting coinage for 0 levels worked out great, with no one having enough money to buy much more than a few slices of bread, maybe a beer, and a place on the floor of either the inn's common room or the stable. Having so little money makes even the recovery of a handful of gold pieces a real achievement!
The first foray into the Caves of Chaos led the characters into the southern, goblin-infested cave. They encountered the six wandering goblins right away and one thing was quickly clear: 0 levels are a match for goblins only with judicious use of tactics. The goblins' AC of 14 made them tough to hit... much more so than the PCs. However, by using lots of pitchforks in the second rank, the PCs were able to achieve parity in kills with the goblins.
Two wounded goblins fled to the southeast (I decided upon a 33% chance that they'd run in that direction instead of towards the core of their lair, and then rolled a 1 on 1d6) and the 12 remaining characters followed in short order. They were slowed up by the need for lighting and then became sidetracked by the dead end passage going east, which they didn't know to be a dead end. The goblins in the next room decided this was an excellent chance to attack and fell upon the rear ranks of the PCs just as the latter discovered they'd have to turn around.
This second battle was rough on the players (they had kept the characters they liked most out of the front ranks in order to protect and save them), but once again the pitchforks made a huge difference and the players held the field. With 7 of the original 16 PCs still standing, the two remaining goblins of this encounter fled west towards safety. In this case, the PCs speed resulted in them catching the humanoids at the junction near the entrance to the cave. The poor goblins screamed "Bree Yark!" as they were cut down, and seconds later the sound of a stone moving followed by a monstrous roar announced a new threat.
Some of the PCs decided to flee the cavern, but a few decided to try to loot the fallen goblins before they were attacked. Several Agility checks later, 2 of the remaining PCs were too tied up with filching silvers to escape before the ogre came calling. The results were exceeding ugly for those 2 PCs.
In short, then, 5 of the 16 characters survived. Between loot gathered and monster experience gained (I'm using B/X xp charts for now), each of the five managed 20xp.
I'm thinking that I'll be running at most three level 0 sessions (third time's a charm, and all that...) before allowing each player to pick a surviving character to advance to 1st level. In the meanwhile, we'll be rolling up 11 more characters before we play next week's session so that everyone has a chance to "shine" once more.