Someone told me a while back that 1999 Series notes with Lawrence Summers' signature had some extra value. Probably because he was treasurer for a short period of time.
No, they made lots of Series 1999 in all denominations. Somebody may have confused the story with the 1963B Barr dollars. Joseph Barr was only the treas. Sec for a month at the end of Lyndon Johnson's term. people saved them because they thought they would be valuable, but as it turns out, they BEP printed them for a period of time after he left office. In Unc condition, Series 1963 and 1963A dollar notes are harder to find than Barr dollars
Update: Taking everyone's advice, I already spent the note (the bill is already in the till at the local grocery store).
I would have made sure it made it to the till at the local bar and toasted my new found knowledge of 1963B Barr Dollars!