Watch Serial Number Database
The above list may prove potentially useful for determining the approximate age of an Omega watch via cross-referencing it's serial number with the date in the table above. Remember that watches were not necessarily sold in order or sold close to the date of manufacturer.
Watch Serial Number Database
A Two-Tone grade 345 'transit' movement Elgin Watch Databases Although it may require some digging, a lot of useful information can be found out about Elgin watches by using these databases. 
Right now, everything is geared toward experienced watch collectors, but even people who know very little about watches should be able to pick out some useful facts. Avatar the last airbender kisscartoon. The Elgin Serial Number database was created by scanning and OCR'ing the 1950 serial number list.
Hamilton Pocket Watch Serial Number Database
Then I had to go through and clean up the list by hand, changing 'O's to '0's, 'S's to '5's, and '11's to '0's etc. Then I wrote some code to do a bunch of sanity checks on the data (serial number runs should increase and not overlap, high grade numbers should appear early, etc.) Then I verified the runs that I found with the runs that Dennis Booth typed in by hand and resolved all discrepancies between the two databases. Next I compared the production totals by grade with the list created by John Miller in Roy Ehrhardt's 'Elgin Watch Company' book.