Our oldest son has always been into fancy writing instruments. Since my wife and I have had home-based offices his entire life he's always had access to a multitude of pens and pencils, and if my favorite pen ever went missing I had a pretty good idea where it ended up: his room.
That's why I think the following will be a pretty cool gift for his birthday (and it's a helluva lot cheaper than a car or name brand shirt):
For those of us who can happily spend hours browsing the aisles at Office Depot, this is big, big news.
"A game-changing liquid graphite that eliminates broken pencil leads forever."
• Writes as smooth as a pen
• Erases like a pencil
• Becomes permanent like a Sharpie marker after three days
Befuddled 
I’m a sucker for office supplies, and I love my paper-and-pencil calendar. This will be a must-have for me, too – it’s the best of pens, pencils, and sharpies (love!) all rolled into one!
Jon,
Great gift to your son!
I have always thought writing implements were special gifts…especially to or from family or friends. Quite a number of years ago I had a real dilemma concerning a gift for my wife. I finally ended up in a local office supply store (I think it was Hinkley’s…no longer in business) and purchased an exorbitantly priced pen and pencil set. She, being an educator and English major, loved the gift and I was safe for another year. Subsequently, she was careless and sometimes left the pen on our table (think desk) and I used it to write a check or sign a letter. When another Christmas was looming, she asked what I wanted and I said, a pen like yours except I want the color to be crimson. Well, for that Christmas I received a crimson pen set with the engraved inscription “Blass”. Now I know that Bill Blass didn’t manufacture writing implements, so I assume she had to pay an exorbitant price …plus some more.
Sorry to be so loquacious, my original intent was to simply say Happy Birthday to your son.
Dwight