Nothing says hi-tech like a pen but I wanted to let you know about a cool new pen I have been playing with called the Pilot Frixion erasable pen.  Unlike other erasable pens, this one actually works very well because of its thermo-sensitive ink that erases clean. 

The Frixion series comes in ballpoint and fine point. 

 

You can see a sample above where I erased a section of my solid line.