If you need to tweet something that starts with an "@" sign or anything that has a dot in it, Twitter auto-converts most of them into a clickable link. In fact, it will sometimes turn them into shortened URLs when it's not even a link. Amit Agarwal of Digital Inspiration came up with a workaround.
If you run into this Twitter issue, head to Agarwal's ZeroWidth tool at the link below, or with the URL j.mp/zerowidth. Type what you need to in the "Enter Text" box, copy the text it generates below the box and paste it into a new tweet. It works with default Twitter and Tweetdeck, and probably with other Twitter clients too.
As Agarwal explains in the video above, this is possible by adding a zero width space to the text. You can't type it in Twitter directly, but with the tool, it works perfectly.
Prevent Twitter from Converting @Mentions into Links [Digital Inspiration]