Every serial number is as rare as the next, because every note has a different one.
In most cases the serial number doesn't matter to the value of any 20th or 21st-century US bill. Serial numbers are counters and security devices and in general aren't items of collector interest. The major exception is bills that have "special" or unusual serial numbers; these are collectible among groups who look for particular patterns or other combinations. Low serial numbers (e.g. 00000003) are highly prized because they represent the start of a particular print run. Other collectors look for patterns such as 12345678, numbers that look like dates (20101225), or "radar" notes whose serial numbers read the same backwards and forwards like 35799753.
The serial number on a Centennial dollar bill, which commemorates the 100th anniversary of the U.S. dollar bill, can vary as each bill has a unique serial number. Typically, the serial number consists of a combination of letters and numbers, usually starting with a letter that designates the series year. To find the specific serial number, one would need to look at a physical bill or a detailed image of it.
You can look up a two dollar bill, but if you mean specific as in serial number, you are the only one that possesses that specific two dollar bill with that certain serial number.
Look up at proofhouse.com
You find a published list of serial numbers for the maker.
Look on the frame.
look on the frame
$1,000,000,000,000
Look on the butt.
proofhouse.com
Serial numbers usually look like a combination of numbers and/or letters. You need these to install and use your games or software. The serial number should be located on the back of the CD case or within the documentation that came in the box.
Serial numbers do not designate calibers. Look on the brrel to ID the caliber.