Bulls, I usually don't even have to put a line on my ball. I use the line that's already on the ball as my line. I used to mark a line or an arrow with a green, blue or red sharpie, but since most balls add a line (or the ProV1 text) on their balls now, I just use that. I love it.
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Texas Wedge
In The Bag:
MacTec NVG2 9.5 deg driver
TaylorMade 200 Steel 3w & 5w
Callaway x-16 Pro Irons
Odyssey White Steel #5 Center Shafted Putter
SkyCaddie SG5
"...I bow to your greater knowledge..." -- Lefty of GRW in response to one of my posts
Winner of three 2007 Golf Rewound Pick Em Contests:
Players Championship, US Open & PGA Championship 
Repeat Champion of the 2008 US Open Pick Em Contest