As incredible as the, err, HTC Incredible may be, there appears to be a pretty serious bug locked in the Sense UI which takes screenshots of the web browser's content, storing them even after a factory reset is done.
You can imagine how major this could become. Banking history, private messages, even your preference for well-oiled animals could be uncovered if someone knew how to find the jpeg screenshot files. According to the tipster which alerted BGR, the jpegs are saved under a folder by the name of ".bookmark_thumb1", under the "emmec" storage folder. It's not known yet whether this issue is confined to just Incredible phones or other HTC Android devices with the Sense UI, but for the love of all that is sacred - please go and delete these files before selling the phone/giving it away. [BGR]
UPDATE: As several readers pointed out in the comments field, the bug stores screenshots of bookmarked sites only, and as they're stored on the microSD card rather than the ROM, it makes sense they wouldn't be deleted after a factory reset. You wouldn't expect your photos and other media to get deleted from the microSD card, so it figures the screenshots wouldn't either. It makes sense, but it still doesn't make it right.