For most everyday things that I'm curious about, I love Wikipedia. It's easy to find information, and the vast majority of the time the information is correct, and most of the time it isn't correct it is obviously incorrect. Same thing if I'm writing an article, and I simply want to provide a link to a definition (i.e. something that doesn't affect the overall argument). However I do cut the line at serious research, or if I'm actually trying to make a serious argument about something, and as others have said will use it as a starting point instead.