I'm a mod at Computational Science SE. Sometimes, users ask questions on Computational Science about doing something in Wolfram Alpha. As far as I can tell, Wolfram Alpha uses Mathematica for its math engine. Are those questions on topic here?
Note: I was made aware of Other WRI product discussion?. I'm scoping my question specifically to uses of Wolfram Alpha that look something like http://scicomp.stackexchange.com/questions/1407/solving-system-of-equations-with-wolfram-alpha, where the question is talking about using Wolfram Alpha for mathematics only.