Seems to be a popular theme right now, so we might as well do it while it's hot. We've already seen some excellent sigs, so it should be interesting and challenging.
There were another couple of popular selections, so I will carry those suggestions over to the next sotw.
Post your entries in this thread and don't forget to disable your signatures.
Try to remember to insert the image link as well.
SOTW #15 (300 sigs) 
Linear Mode
