Remember that anonymous users can make anonymous suggested edits. Therefore, effectively at 0 rep (the lowest reputation on the site is 1 rep, which gives you privilege to ask and answer questions, anonymous user doesn't even have these privileges), you can view any deleted post that is not locked, and any deleted+locked question if you can guess the id of the answer (possible on sites with low traffic at the time that the original question is written).
For demonstration, let me use this deleted question: http://meta.stackexchange.com/questions/82538/eeeek-what-happened-to-my-envelope (404 - we know it is deleted)
Make sure to log out of your account before trying these links (since it seems some mechanism is used to prevent users with low reputation from opening the edit link).
This bug has been fixed by 3-Jun-2013, since it seems to allow silent edit to deleted posts by user without full editing privilege (less than 2k). Allowing write operation without the privilege is quite dangerous. Therefore, the bug was promptly fixed.