Twitter Audio is one such free application which lets you tweet your recorded voice with text on twitter. In order to tweet your voice you just need to record audio from your microphone and then you can append the text upto 110 characters.
It is very simple to use, record your message, type in your message of 110 characters and press the Tweet! button shown in the image above.
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Then after your tweet will be posted in the following format at twitter – "text + file url". You can listen the audio by clicking the link posted with the tweet.
See Also: TweetThisText – Highlight Any Text On Any WebPage and Tweet It On