You have a stuck pixel, not a dead one. A dead pixel appears completely black and cannot be fixed, but a stuck pixel is stuck in the "on" state and appears blue, red or green.
The good news is that stuck pixels can be repaired, the bad news is that it doesn't always work, and when it does, it can take a long time.
You were on the money when talking about flashing colours rapidly, as it delivers voltage to each pixel, prompting it to change state.

I can't recommend any program to do it for you, because I wrote my own in Java (very easy), but you'll find heaps of programs and videos of flashing colours if you google for them.

I've repaired stuck pixels in my laptop, flatpanel and PSP with this method, but bear in mind some took days to come right. Sometimes doing what rubah said will fix it but I've had more success with the colours.