I know this is an old thread, but please note that Celko and Improved Celko are the only ones (of the non-CLR ones in the test harness, as written) that survive crossing into BIGINT values (i.e. over 2147483647 but less than 9223372036854775807).

Trivial extensions of some of the others results in errors, probably due to rounding, at least near the maximums.