For U.S. residents only.
After 12P (CST) - 1P EST go to
Experience uni Super Ink
for a free uniball superlink pen, similar to a roller.
If the quantity is exhausted for one day, try the next day.

This not an unlimited offer. But from experience they offer free pens about twice a year.

Heh, interesting.
Do they ask for any personal information (other than an address to ship to)?

I already have plenty of pens (one of the many benefits of being in high school), but free stuff is always nice.

No.
Just an address to send the pen.
I have one the pens from a previous offer.
Smooth writing.
The idea is give out samples. If you really like the pen head over to Staples and buy a few.
Normally in the house I use fountain pens. But I keep the Uniball in my coat. Seems to write similar to the Fischer Space Pen from years ago.

Might be obvious, but just tried it and its all gone

I see these kinds of tricks on Facebook all the time.
The idea is to give you a sample of the product for free, with the idea of you buying the actual product later.

This is not a trick.
You are getting a pen directly from the Uni Ball manufacturer.
I believe they run the give away once a year.
I received a pen in 2008.
I should be getting the 2009 model in a few weeks.
The idea. Uni Ball wants you to try out the pen, so you will buy others.
The pen is a bit different from other pens. Very smooth writing.