Please post a new question with the bill's denomination, date, and what letter if any is next to the date.
This means that that note is a replacement to a damaged note. These usually have a value above face value but not much more. For example you might get $1.50 or $2 for a star $1 note.
A denomination is needed. Please look for questions in the form "What is the value of a 1928 A US [denomination] dollar Federal Reserve Note?" for specific information.
What is the value of the shortest note
The green seal indicates your bill is a Federal Reserve Note. Please see the question "What is the value of a 1934 US 5 dollar Federal Reserve Note?" for more information.
The green seal indicates your bill is a Federal Reserve Note. Please see the question "What is the value of a 1934 US 5 dollar Federal Reserve Note?" for more information.
The green seal indicates that it's a Federal Reserve Note. Please see the question "What is the value of a 1928 US 5 dollar Federal Reserve Note?" for more information.
Unless it's an error note, any US bill dated 2006 is too new and too common to have any extra value.
About $3.
The green seal indicates that your bill is a Federal Reserve Note. Please see "What is the value of a 1928 D US 5 dollar Federal Reserve note?" for more information.
Could you check your bill again? A red seal would indicate that your bill is a United States Note; the first $2 FRNs were dated 1976 and have green seals. If you have a US Note, there's more information at the question "What is the value of a 1928 US 2 dollar bill?"
The largest denomination of currency the US prints today is the $100 bill.
Your bill is called a United States Note rather than a promissory note. There were eight different subseries within the 1928 series date; please see the question "What is the value of a 1928 US 2 dollar bill?" for specific information about values.