USB flash memory has recently been tumbling down in price, and now you can carry around all of your important files for less than £20.
That said, most budget drives hide a substantial issue; speed. If you are routinely copying large files, a slow transfer rate can mean the difference between going to the pub and staying at the office for an extra 5 minutes. A serious problem indeed.
Due to the drop in price, faster drives are also available for more accessible prices featuring larger sizes too. Today I have the OCZ ATV Turbo 4GB USB drive that should be able to store your stuff and make transferring a quick job.