The pen, once mightier than the sword, has been getting trounced by the keyboard in the computer era. Now and then there’s a push toward “pen-based computing” that doesn’t get very far. However, in a test of the latest crop of pens that combine ink with digital technology, at least one stands out as a useful tool and a complement to the keyboard. All three pens I tested record what the user writes, and can transfer an image of those notes to a PC. The standout of the group is the LiveScribe Pulse.