Dial in to Asterisk to break out

Is it possible to set up an extension in Asterisk to allow a user to dial in from a cell-phone and then pick up an outbound line to make a call out using asterisk.
This would allow users who are travelling and without internet connections to make their international calls via our Asterisk, and not have to pay the cell providors a fortune.

I know this sounds kind of odd, but I want to set up least cost routing in Asterisk for international calls so they go something like this…
Cell user only ever dials local country number to dial into Asterisk>>

Gets asked to enter a pin>>
Pin is verified, user is able to dial international number which Asterisk routes by the best method.

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Yes. Read about the DISA feature here.

voip-info.org/wiki/view/Asterisk+cmd+DISA

Excellent, Thanks…

Sounds a lot better than my explanation as well

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