Limiting browsers to sites

[spober at manvax.cc.manhattan.edu]

We want to limit certain of our public computers to browsing our
catalog and specific web-based periodical indexes.  

I know that some of the filter products (Net Nanny, for example)
claim they will do this.  Has anyone evaluated the filters for THIS
use.  We're not interested in using them for their more common claim
to fame - blocking sites they consider objectionable.  But from what
I could tell on the TIFAP page, they were not assessed for this 
particular use.

Can anyone point me to reviews of filters that assess their ability to
limit users in this way (not to a list of 'family-friendly' sites but
to sites that WE choose.)  Or is there some other type of software that
could do this for us?  (And which might be cheaper than the filters.)

I'm sure there are sites doing this.  Please share what you find worked
well - or poorly.

TIA
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 Stacy Pober			   Internet: spober at manvax.cc.manhattan.edu
 Information Alchemist		   http://www.manhattan.edu/library/mclmenu.html
 Manhattan College Libraries	   Phone: 718-862-7980                    
 Riverdale, NY 10471	     	   Fax: 718-862-7995                    
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