Marco Buttarini

wg-twitter-widget is THE widget to show twitter status in wordpress sidebar. 
Developed starting from the existing widget of Sarah Isaacson, * using the example widget of Justin Tadlock

WG Twitter Widget

Twitter Widget Highly configurable, with image and last twit of users

ArnaudBan

A Widget to show your latest tweets. Use the oEmbed methode and some cache. It is simple, elegant and it works.
This plugin uses the Twitter API version 1.1. You have to authentify yourself ! 
Visit the option page “Settings->Widget Embed Latest Tweet” to do so.
Options :
<ul>
<li>Number of Tweet to display</li>
<li>Maximum width</li>
<li>Alignment (left, right, center, none)</li>
<li>Choose your language</li>
<li>Hide the original message in the case that the embedded Tweet is a reply</li>
<li>Hide images in the Tweet</li>
</ul>
Note that with the oEmbed method you can not customise easily the display of your Tweet. 
However, the oEmbed method ensures you that all Twitter’s recommendations for displaying your tweet are respected, they are providing the code !
If you want to help <a href="https://github.com/ArnaudBan/widget-embed-latest-tweets" rel="nofollow ugc">the code is also on github</a>

Widget embed latest Tweets

A Widget to show your latest Tweets. Visit the option page "Settings->Widget Embed Latest Tweet" to authentify yourself

WG Twitter Widget vs Widget embed latest Tweets