Great topic! I mark my ball with a thicker line on the aim marker and 3 dots below or above the Titleist logo. For some strange reason I can't play a ball without it lol.

Cheers Shawn

I mark my balls with 3 dots the resemble the Cameron cover that I have. One day my son colored a whole dozen of new ProV's with the sharpies in my bag and then I stuck with it. I only play with #1's.

Brian

I use a blue marker to put a 'cat paw print' between the Titleist logos. I have three cats so thought that would be a fitting mark.

I rock a big green dot next to the number on the right. My ProV's are all 7's and say Giahitsauce so they're pretty recognizable. 

For 2013, I think I am going to go no mark, and just have the custom number 96 on them.  I like the clean look, and 96 is my favourite number.  

For 15 years its been two red dots above and below the aiming line...love my ProV's :)

I've got my ProV's stamped with my "trickey" :)

I make a "happy face" on the side of the Pro V that has no markings. This helps me to recover and feel good if I hit a bad shot!