OK, this is embarrassing but our solution was buying a pair of walkie talkies. 
On the back end, we have a schedule of who is "the backup" person and they carry the other walkie talkie around with them and don't leave the building during their backup hour. But they can be in their office, in the stacks, wherever.   1940s tech FTW.   Of course, building an app would be more fun. But in the meantime, this costs about $30. 

Jenny Reiswig
UC San Diego


On Feb 21, 2013, at 11:28 AM, "Kyle Banerjee" <[log in to unmask]> wrote:

>> At a meeting recently, I was listening to a work leader lament how, if
>> she is the only person there, she is just too busy to make a phone call or
>> send an email asking for help - a common occurrence.  After I heard her, I
>> wondered how possible it would be to create some sort of desktop 'app'.
>> One that requires only one click and is smart enough to know its service
>> desk location and is sent to the right folks who could come assist right
>> away, upon demand.
>> 
> 
> The low tech way to achieve this would be to just have a shortcut pinned to
> the windows task bar that triggers a web service. A variable passed along
> in the URL would indicate your location which would be transmitted in a
> canned email to everyone. For added reach, the web service could ping
> peoples' cell phones. Any of your local systems people should be able to
> whip this in less than an hour.
> 
> Regarding the windows messaging service suggestion, that doesn't seem like
> an improvement on email (also, those types of messages are frequently
> blocked).
> 
> kyle