Removing many reports

I have figured out how to remove a single test from one host, or all tests from a single host. Is it possible to remove a single test from *all* hosts? Or all tests from all hosts? Or all tests that are purple?

I.e, are there Hobbit equivalents to these Big Brother tricks:

cd bbvar/logs

rm *.sometest

rm *

ls|xargs grep -l purple|xargs rm -f

Ulric