I've written about Livescribe before (Livescribe Pulse Pen - Pure Awesome) and if you're looking for a great gift for the geek in your life, or for a high school or college student, I don't think you could do much better than the Livescribe Echo, the updated version of the pen I use.
What makes this pen so cool is how well it changes your experience taking notes. In my case, I almost immediately stopped taking my laptop to meetings - it occasionally shows up now, but I am far more likely to take hand-written notes. Practically, it means I'm less likely to check e-mail, respond to IMs or otherwise get distracted from the meeting I'm in. The notes you take are then synched back to your PC, and fully searchable. Any audio recordings on the pen are matched to the time you took the notes, so that you can tap the page and re-hear the discussion at the time - extraordinarily helpful for clarifying notes that are unclear.
The pen's ability to record the audio of the meeting has, on several occasions, radically changed my ability to benefit from the interactions during the meeting. One example comes to mind: I had a big presentation before a number of execs, and my team and I had a series of prep meetings to go over the presentation. Ordinarily, I'd have someone else run the presentation so I could try to take notes on my computer while keeping up with the conversation. With the Livescribe pen, I instead drove the deck from my computer, and didn't take any notes. I just recorded the audio of the entire meeting - I was more engaged in the discussion as it played out, and after the meeting, I simply replayed the audio while reviewing the slides and incorporating the suggestions that were made. The end result was a presentation that more faithfully implemented the feedback of the entire team, and I had complete confidence that I hadn't omitted any of the valuable input we'd received during the prep.
If you're looking for more on how the pen works, Scoble's interview with Livescribe's CEO is a terrific review of how it works:
The Echo pen has a better form-factor than the Pulse (the model that I have), uses standard micro-USB and headphone connections, and offers improved software on the pen itself. Can't recommend this pen highly enough - really a great product. Oh - and I am also a big fan of their moleskine notebooks for taking the notes themselves.
(Disclosure: I happen to be friends with one of Livescribe's founders. As I noted in my original post, he gave me a Pulse pen a while back.)