opnsense-ports/math/add/pkg-descr

Add is a fixed-point calculator that operates as a full-screen editor.
Add performs fixed-point computation. It is designed for use as a 
checkbook or expense-account balancing tool. Add maintains a running
result for each operation. You may scroll to any position in the 
expression list and modify the list.

WWW: http://dickey.his.com/add/add.html