My company's contract web designer and I once developed a demonstration of an e-commerce site in Perl while I was driving from Chicago to Kansas City to present said demonstration (note, someone else was driving the car while I was writing code!). Please keep in mind that our designer was remotely deploying templates to the web server running on my laptop, which was connected to the Internet with a blazingly-fast cell-phone dial up connection :P

(for future reference, it's not the most efficient development process, but it worked!)

MrCromeDome