If you write academic papers, feel free to try out my Reference Checker. It's a free online tool for cross-checking all the references in a paper with the bibliography. It has even been called "one of the best things you can find on the internet" (and not by me)!
I'm the creator of Dexter, a suite of software tools for the analysis of linguistic data. It's free software that helps you do detailed analyses of spoken or written texts. Feel free to try it out!