I routinely try to find party ideas that are unconventional and out of the box. I think that Youtube is generally a good source for this sort of tips. All you need to do is browse Youtube and do a search for "birthday party suggestions" and you are going to see several hours worth of online videos with a lot of very good suggestions. The problem is, who has the time to see them all? So I am on a regular mission to collect some notes so as to save me and also hopefully others some time.
Here is a great video with some insane party ideas - https://www.youtube.com/watch?v=wUlJSgYGmFw
Hope you see a few great ideas for your upcoming celebration on Youtube!