I wanted a quick and simple way to just automatically link to a Twitter userpage or Twitter search whenever I wrote them in a blog post. The Answer to this is my Tweet WordPress plugin (previously known as Autolink to Username). The other plugins were full featured or only linked to the username in the sidebar or widget.
For example here is my twitter user: @lantrix
Here is a hashtag example: #australia
Download the Tweet plugin from the wordpress plugin directory.
If you like the plugin, I do accept donations as thanks.
Installation instructions are in a separate post for the release.