How to manually enter a name in a field

[mgreen]

Hi - I have a field labeled "reporter."  It allows me to choose and select from a dropdown list of all the reporters that have been entered into our system. Is there any way to manually add someone into a cell in this column who is not on our list of regular reporters (i.e. a one-time freelancer)? Please let me know if you have any insight into this. Thank you! 

[gady]

In grid mode If you just type in the new value it will add it to the list

In Form Mode, you can't