I couldn't help but crack up when I read a post about Tripeedo, an AJAX-enabled "command line for travel," since of course all this reservation searching stuff was on a command line to begin with, on a terminal a generation older than this hideous beast. And in fact while the hardware has mercifully been emulated away, the protocols are still in wide use under the hood in the travel industry.
I had to use a command line like this as recently as 2006 for a project. Unlike tripeedo's version, I recall the search started with a strange lozenge character that doesn't seem to have a proper Unicode name, but was part of the 6-bit EBCDIC charset these terminals used when they were deployed in 1969. Then came a letter or a delimiter of some sort, and then a line like 15AUGSFODFW to look at flights on August 15th from SFO to DFW.
I thought I'd try it in Tripeedo. The site prefers the month first, and it likes spaces. And, unlike the old system, it has lowercase letters too!
So I type "15 aug sfo dfw" and get some flights to look at. In 1969, this was the future.