I’ve never found a social sharing plugin for wordpress that I liked. With my old site I resorted to adding the social sharing icons (Digg and Reddit) manually to the html and php but since then a few more social shares have popped up: Facebook like, Facebook share, Twitter share, Google Buzz etc.
Most of the wordpress plugs have a rollover popup of some sort with hundreds of tiny icons for every social network on the web, recently however I have come across Simple Social - Sharing Widgets/Icons.
Simple Social - Sharing Widgets & Icons in my opinion has the import networks Digg, Delicious, StumbleUpon and Reddit but also has the all important Facebook “Like” button and the new Twitter button. The plugin also gives you a choice of small or large icons which look lovely. Download Simple Social - Sharing Widgets/Icons