I've found some fun Drupal modules that I wanted to share. These are low-maintainence, easy-to-setup background modules that will compliment most blogs and "fun" websites.
Add an image field to a content type and select that image to appear as the website background image, see here for an example.
Use a cookie to display a popup (browser) or redirect to a page (mobile) when a user visits a site. You can update the page it appears on and the frequency of when it's displayed. Works with colorbox.
Enter any arbitrary keystroke on a page (eg. the Konami Code) and load an action such as displaying images, falling snowflakes, loading the asteroids game, etc. There are several actions available in the module and it's pretty easy to add your own. This site currently loads browser ponies when the Konami Code is entered.
On International Talk Like a Pirate Day (September 19th), this filter changes all appropriate English phrases and words into pirate-speak.
This novelty module converts english text into a variety of silly formats such as Pig Latin, l33t, etc. Similar to the pirate module.
Generates random quotes from the movie The Big Lebowski
Have a user on your site you don't like, or are you just a BOFH? This module makes life difficult for certain users and is an alternative to banning or deleting users from a community.