I tend to use NoteTaker for "heavy duty" note taking, relating to very specific things. (i.e. A Notebook for a particular software project, etc.)
However, a really simple way of keeping quick notes that can be easily accessed is to simply install a Wiki running under your Apache server. The simplest one that I have found to wit is the UseMod Wiki. Simply drop the wiki.pl script into your Apache "CGI-Executables" directory, make a few modifications (where to store the WIki files, etc.) and everything "just works". I use the Wiki to keep links to "Other Stuff", to take quick notes, or links to other documentation in one place. (Links to local copies of Java, Python, Ruby documentation, project notes & ideas, etc.)
The cost is also right (can't beat "free and open source")...