Hopefully you have a bunch of your favorite brush, swatch, symbol, and graphic style libraries saved for easy use when working in Illustrator (If you don't know how to save a library, check out the previous Saving VM Elements To Illustrator's Libraries post). If you have a user defined library that you need in every Illustrator document you use, Illustrator has a pretty nifty setting.
From the pop-up menu of your user-defined library, select Persistent. Now whenever you create a new Illustrator document or open an existing one, your persistent library will be there. Sweet!