Exporting from Aperture!
This tip is especially useful if you are used to how iPhoto works and you are now using Aperture. In iPhoto, you can just drag a photo out of the application directly to the Finder. With Aperture, the exported photo won't have full resolution. The only way I found to have a full resolution Jpeg out of Aperture is to use the Export menu. From there, you can choose the resolution of the export. If anyone knows of a way to export directly by dragging the file out of Aperture and getting a full res export, please post about it in the comments.