Yes, the fun thing about stamp collecting is that after 100 years, discoveries are still made as today's example shows.
At this weekend's Mid-Cities Stamp Club annual EXPO, I found yet another example of a St. Vincent ½ Penny forgery. This forgery was probably produced in the late 1880's (to defraud collectors, not the post office). Yet after all these years, no collector, dealer or other specialists seem to have noticed these forgeries as there are no write-ups about them anywhere!
So, keep lookin', you'll never know what you'll find!