The one at MIT, Nightline, was smart because it pitched itself as a general "call for any reason at night" number -- I called a couple times to get urgent help (after someone tried unsuccessfully to mug me, and I needed to figure out who to report to) -- not just for suicidal people. I suspect there are depressed people who may ultimately kill themselves who, if there were some number solely for "suicidal people", wo…
The biggest problem seems to have been that word got out about it outside the MIT community, so that they were getting many calls from non-MIT people. But, their policy was to try to help anyone they could: http://tech.mit.edu/V130/N43/nightline.html
Maybe it would have been better to change the policy than to scrap the whole service.
(BTW I was one of the first Nightline staffers back in 1978.)