Forget incogtweet, i don't think it works any more.
.........
I have just used swarmsecret to send those videos to several celebrities, it's a tool for sending tweets anonymously.
Also, here's a tip:
"Twitter assumes that if you begin your tweet with an @ reply then it is only of interest to you and the select group of your followers who also happen to be following the person you are addressing your message to.
While that may indeed be the case, it limits potential interaction between your followers who might NOT be following that individual but who might genuinely be interested in the conversation you are having with them."
"Luckily for you there’s an easy fix to make sure everyone sees your tweets. Simply put a character before the @ reply and suddenly Twitter thinks you want the whole world to see this tweet.
Experience has proven that using a ‘.’ before the @ reply is about as unobtrusive as it gets"
http://sproutsocial.com/insights/how-to-make-sure-everyone-sees-your-tweets/
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If you can't use your own twitter account (which is better because the person can reply to you)...
You can just go to this page, type in the box
'.@twittername' and then your message.
It will be sent to them anonymously and will also be seen by swarmsecret's 5000 followers.
http://swarmsecret.com/
........
Here are a few I did earlier:
https://twitter.com/swarmsecret
That's enough from me, now who wants to help out?