I played a bit with this and you might be able to get it to work with a report link field if you are willing to have the users key a record ID# of the project they are trying to link to. Or any field on the record that they want to link to if you have a better field than record ID.
I made this field
Right("000000" & ToText([Record ID#]),7)
and then this other field
List(",",If([Other project 1]>0,Right("000000" & ToText([Other project 1]),7)),
If([Other project 2]>0,Right("000000" & ToText([Other project 2]),7)),
If([Other project 3]>0,Right("000000" & ToText([Other project 3]),7)))
ThenI used these fields to make a report link field and set it to not match exactly.
