As for some WebQuests, I found this one involving math in video/board games, as well as thh entertainment industry that I thought would really grab students attention. Not to mention, it answers the age old question, "When are we ever going to need this?" I think it really makes the students realize how important their math skills really are in the world. That and it also gives them a chance to put their knowledge to work by playing a few math games at the end.
The URL is http://questgarden.com/102/36/1/100426171111/index.htm.
Another WebQuest I liked was this particular one because it has a good idea behind getting students prepared for the ACT. With more and more of teaching being data driven and a lot of that data is based off ACT scores, I think this WebQuest does a lot to help students prepare without overloading them on a single topic. It allows students to focus on a single idea, then has the rest of the students "teach" each other the topics which they did not research.