I know that problem, as I am an horrible procrastinator too. I have a tendency to do things just before it's too late, or worse right after it's too late. Delaying them for random things ranging from making tea to answering you. In fact, anything that isn't quite useful compared to what I need to do. (ie. paying taxes - I just realized I've got only five days left).

So anyway, I don't know about the "promise yourself you'll work after five minutes" but I don't think it would be very useful - I've been telling me for something like 2 months that tomorrow, I'll pay my taxes. What I know does work, if a little, is disassembling what you have to do in little bits, and doing them one by one, then doing your average random stuff inbetween each little part of what you had to do. Still you won't be as productive as someone who doesn't have that issue, but at least things will get done. Hopefully in time.

Be organized. You'll have to organize yourself more than the busiest businessman in order to manage to achieve something. Use agendas, calendars (I figured Google Calendar with its mail reminders is good, and it's online so you put it as your homepage and everytime you start your browser it bumps in your eye). Maybe consider buying a PDA. I don't have one (too expensive) but a friend of mine with the same problem has and he tells me it helps him a lot.

And document yourself about Attention Deficit problems (ADHD probably the most known). It doesn't always apply, but your problem could be deeper than you think.