Background Generator
Put this between your <HEAD> and </HEAD> tags:
<META HTTP-EQUIV="Site-Enter" content="RevealTrans(Duration=3,Transition=23)">
That looks a bit technical, let's look at the parts of the tag in more detail:
HTTP-EQUIV="Site-Enter"
This command tells the browser to be ready to do something when someone enters the site. What the browser will do is determined by the next command (content=" ").
content="RevealTrans(Duration=3,Transition=23)"
This command tells the browser to perform a transition. The duration and transition type are defined inside this command, here is what they do:
Duration=3
This determines the amount of time the transition will take from its beginning to its completion. The number is in seconds, so in this case the transition takes 3 seconds. You can change this number to make the transition longer or shorter.
Transition=23
This determines the type of transition that will be executed. There are 24 transitions at this time, with the numbers from 0-23. Transition 0 reveals a square from the outside in, and displays the page. Transition 23 displays a random transition from 0-22. You can view all of the transitions by their numbers with examples on the Transitions: By Number page. Once you have found one you like, replace the 23 with the number you desire!
Exit Transitions
Transitions can also be done when a viewer exits the page. The META tag is almost identical, but it performs the action on a "Site-Exit". Again, place the tag inside your <HEAD></HEAD tags:
<META HTTP-EQUIV="Site-Exit" content="RevealTrans(Duration=3,Transition=23)">
Again, you can choose the transition you desire using the Transitions: By Number page.