It's certainly possible. There are also commercial addins that will schedule
emails to be sent on a regular basis, but I don't know if those will forward
messages.
Would this be Outlook VBA code or a COM addin done in VB6 or VB.NET or ...?
You need a timer and some logic as to what emails are to be forwarded. You
can search at
www.outlookcode.com for "zaphtml" to find code that will
handle emails being delivered to Inbox. That strips out HTML but can be
adapted to do anything else with those incoming emails including forwarding
them to a specific email address or cell phone if it has an SMTP address.
What sort of timer to use depends on what you have installed in the way of a
development system and how good your coding skills are. For example in VBA
code you can use a Win32 API system timer but that takes tons of obscure
code. If you are coding in VB6 or VB.NET you can use a timer control
provided with that development environment.
This link has code for a VB6 high res timer but can be adapted to work in
VBA code, as one example:
http://www.vbaccelerator.com/home/vb/code/Libraries/HiResTimer/article.asp