Hopefully it's okay to bump this.
Recently I've been playing around with shaders that are included with DOSBox SVN Daum, and discovered one called CRT-geom-curved.fx that produces an imitation of a curved CRT screen:
Here's a video of Prince of Persia being played with this shader: YouTube link.
My memory of an actual CRT monitor that I used to have a very long time ago is quite hazy, however many people whom I've shown this say that the resulting image does not look like an actual CRT computer monitor. After some Googling I also discovered that the CRT-Geom shader bundled in DOSBox SVN Daum was originally written for console emulators and as such attempts to imitate a CRT TV screen, and not a computer monitor (here's a very detailed description of the console emulator version of the shader).
The shader itself is quite customizable (by editing parameters within the shader file), and it allows for example to reduce the curvature of the screen and the roundedness of the edges:
It is also possible to turn off the curvature entirely if desired:
I wonder if it would be possible to tweak some parameters in this shader so that its output resembles an actual CRT computer monitor more than it does now?
It is also worth noting that DOSBox SVN Daum includes a different shader that aims to do the same, CRT.D3D.fx (it is also available from Gulikoza's website). It produces a slightly less curved but not entirely flat image: