maximillianos - 2:11 pm on Dec 10, 2010 (gmt 0)
I would agree it is "not advisable". Can it be done? Sure. Could it create a nightmare in maintenance down the road? Yes.
With today's technology you can have a cms based site that looks and acts just like a static site, but more flexible.
If cost is an issue, you could explore open-source products. If technical ability/limitations on a server is a problem, then I could see using html files with SSI headers, footers and ad slots.