Remove the 150 signature requirement (or lower it significantly) to make a petition public.

There aren't an unmanageable number of petitions on this site right now, so why restrict viewing those that have less than 150 signatures...especially with the existing search mechanisms in place.
You can always add an option to ignore those petitions with fewer than 150 signatures in the search, but I believe choosing the "popular" option does that well enough.
Some of us just don't know 150 people, but that shouldn't invalidate our suggestion.