Simple Text Updates: Is this possible?

[birgi]

Hi everyone,

I basically want a solution that will allow me to manage ONLY the text content of my websites.

Here's the process:

1. I design a website
2. I insert Server Side Includes where the text should be (The text is stored in separate files for convenience)

Q: Is there a web-based, open source solution that will allow my client to edit just the text, and update it?

or

Q: Is there some CMS system that will allow me to place "snippets of code" (like SSIs) throughout my site - then the CMS replaces these "snippets" with the associated text from my client?

Thanks!