Plus! has all sorts of hard-coded limitations for this, for example you can't flood people with chat messages. Even Messenger has similar limitations, like a nudge flood protection. The only possible thing I can think of would be a toast spamming script by blocking and unblocking people or quickly switching status, like Hopper Live. But luckily, that script also has built-in limitations!
Sorry, but abusing the scripts system isn't a good idea. I understand that you want to pester your friends a bit, but I doubt it'll still be funny for them if you make their Messenger crash. I personally think there are better ways to impress your friends than flooding them with IMs.
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