I think it kind of depends on why you want to hide your source?

If there's some sensitive information you need to pass between pages you could stick in the session instead, or even better in a database!

If you are trying to protect the uniqueness of your design, why would you bother?

There are many thousands of free templates available on the internet, see the list below for a very small selection of sites offering these, so it's hard to see why people may particularly target your design for appropriation.

IMHO it is better to distinguish your site from the competition through superior content and functionality coupled with ongoing innovation - good design should be shared - that way the internet is a better place for all of us

Some Template Sites:
http://glish.com/css/
http://www.oswd.org/
http://webdesign.about.com/
http://www.webzonetemplates.com/
http://www.webdevforums.com/
http://www.basictemplates.com/

"Only the guy who isn't rowing has time to rock the boat." Sartre