Anything is possible ;)
I guess you could just extend your user profile to include a field to contain html and then use FCKeditor to allow them to create a page (like with CMS). Would be quite restrictive as they will have on page and that is it but this may suit your needs. If you want this accessible from other site members you may have to do something different to allow this profile attribute to be visible by all.
Something that would be nice (and quite simple to implement) is some URL Rewriting logic so that you can give each user their own personal address i.e.
http://www.example.com/Joe_Bloggs or
http://joe_bloggs.example.com.
You can then parse the user name to load the correct profile page.
Hope this helps