We seem to have a lot of hits resulting from searches for pages which simulate colour vision deficits.
There is an interesting plugin for the Google Chrome browser which attempts to simulate colour vision deficits, and also attempts to recolourise a webpage so that a colour deficient person might see it more like a normal would. Its purpose is more to attempt to aid a person who might have issues with certain colours on certain sites, rather than an attempt to give them a taste of what normals see.
Because the algorithm cannot adjust for each and every individual’s deficiency, it is at best a simulation, but if you are interested it can be downloaded from the Chrome Web Store. It doesn’t seem to work with every site, but it might be worth a look.
Our simulation pages used a similar concept to produce them and are available here. (Just realised that the new masthead I added does not adjust properly, will need to correct that in the coming days!)