Not as comfortable as the old tool, but it does show all nonstop and direct options from any city served by *A: http://www.startimetable.com/StarAlliance.pdf

The destination is of course a question of availability of award seats and how many miles you have available. First class options are limited, TG to BKK or NH to NRT could be doable, however SQ on 77W and 380 are off limits unless you have an awful lot of miles in SQ Krisflyer. Examples for a good business classes from LHR would be NZ to LAX and HKG or AC to many places in eastern and western Canada.