due to my masochistic tendencies i felt compelled to experiment with rails and jquery. i wanted to see how easily i could embed ajax into the design whilst keeping it fully unobtrusive (ie: it still works with JS turned off). I think i'm there with a "single page load" solution. Only loads once, everything after is ajax, both frontend and backend cms. On my demonstration there is no caching and i am still playing with it. Works today, broken tomorrow.
It's maybe a bit OTT (?) but i combined it with an SME solution for peeps requiring a non-transactional web presence. I'm kinda proud of it. Never seen a single-page-load solution before and it taught me a lot of about structuring CSS, i had to rework it many many times.
A friend described it as an anti-pattern, but i think that maybe a bit of a cliche.