Google Makes New Search Operators Available to Gmail Users
Alex over a Google Operating System has a list of the new operators along with examples that show how they work (with your Gmail account).
You can find a list of all Gmail search operators here.
All of these operators are not only be useful when needing to find an item(s) but also when creating/modifying Gmail filters.
About Gary Price
Gary Price (email@example.com) is a librarian, writer, consultant, and frequent conference speaker based in the Washington D.C. metro area. He earned his MLIS degree from Wayne State University in Detroit. Price has won several awards including the SLA Innovations in Technology Award and Alumnus of the Year from the Wayne St. University Library and Information Science Program. From 2006-2009 he was Director of Online Information Services at Ask.com. Gary is also the co-founder of infoDJ an innovation research consultancy supporting corporate product and business model teams with just-in-time fact and insight finding.