Here's a cut-n-paste from my notes for an adventure where the PCs are forced to travel to a drow city. It's inspired by something I heard on NPR about a ramen place in Japan (
http://www.npr.org/templates/story/story.php?storyId=1604880).
Hehehe, the ranger in the party failed his Con check to get a bowl (and the chef smacked him with a big iron spoon), used a hat of disguise to cut back in line and, when he finally got his food, rolled really low on his Fort save. The other PCs, spellcasters, made their saves and didn't get sick.
Ramen-Toa
Baanjopoolp promised to get the PCs a space in line to the most popular food cart in the Arch. Normally, one has to wait hours to get a steaming bowl of greasy noodle soup, but Baanjo pays beggars to stand in line for him. Sometimes (ok, most of the time) line-cutting leads to a fight (this is a chaotic drow city after all). In this case, the group cuts in front of a Large humanoid wearing a hide cloak. It is a hungry maur, who welcomes the chance to stretch out for a good row.
The reason for this long line is that ramen-toa smells so good that one must make a Will save (DC 12) to resist jumping in line. And because of the magical nature of one of the ingredients (see below), it just gets harder to resist after eating just one bowl.
Once they make it to the front of the line, an old fat kuo-toa named Fuku-Ando serves up either a small or large order of ramen-toa. Just like Seinfeld’s soup-nazi, Fuku-Ando suffers no deviation from his strict rules. It takes a Concentration check (DC 15, but Baanjo helps out for a +2), just to get a bowl! If a character manages to follow the rules and get a bowl, he may try to finish it (Fort DC 20 for small, 25 for large). Anyone who cannot finish a bowl will not ever be allowed to have another and may even be attacked by other patrons.
Of course, as good as the ramen-toa is, its hell on your digestive system. Ramen-toa acts as a magical poison with two affects: the mundane effect of cramps, diarrhea, gas and other unpleasantness caused by the greasy noodle soup (Fort DC 20 primary: sickened 1 hour/secondary: nauseated 1d4 hours, second saving throw is made after one hour, not one minute as is usual); and a magical weakening of the will (no saving throw) from the cranium rat brains. The magical effect manifests as a –4 penalty to Will saving throws that is reduced at the rate of one point per day (e.g. –3 after one day, -2 after two, etc.). The penalty to Will saves goes completely unnoticed, but may be removed by a remove curse. This is the effect the mind flayers intended when they introduced the cranium rats into the Throat.