Hi matt
Never had experience with barcode tickets apart from the airport, but I do have a bit of experience with barcodes. You'll probably know there are lots of different types such as 2d, 3 of 9, 2of5 interleaved ect. The biggest problem I've had with bar codes are making sure the software being employed can read the appropriate format, and that the print quality is suffecient enough for the barcode reader. 3 of 9 bar codes for example need to be 27 point font when printed at 300dpi. Since web pages print at 72dpi then the font size would be hugh.
Best out of them all is the 2d barcode as it holds huge amount of data is a very small space.
You can find out a bit more about them here:
http://en.wikipedia.org/wiki/2D_barcode#2D_barcodes