Here was my first thought:

But, unfortunately they do not allow swearing.
Rules: we can have two different slogans, and each one can have two lines of 8 characters each, and they must be G-rated.

Another try:

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I did have one idea that might work but not sure again that 8 letter thing makes a lot of stuff not work. Maybe you could base what you wanted them to say on what the party was. I do think that staying with some form of (e:strip) is a good idea, wish I was more help.
Community is slightly too long, and unfortunately we can't do user names because we only get 4 lines total.
Does Internet Community when I spell it out it looks to long but when I counted it out it worked. Not to throw more things at you but to bad you couldn't get all the (e:peeps) names on one (some are two long) but maybe all the ones of peoples names who fit. Here are two more Ideas since what ever party it is will be at (e:pmt)'s that might be and Idea or maybe "The 24" or maybe even (e:Linwood) again these are just a few ideas maybe some other people will have some good ones.
I was going to get the standard 5-color mix, but there are a bunch of different possibilities.
how about using the word BUM instead?
And can't you choose which colors to use also?