AddThis

With AddThis you can easily share any content to the most popular services including: Facebook, Twitter, Reddit, Delicious, Digg, StumbleUpon and many more.

How to use it:
1. Select the tab with content you want to share.
2. Click extension's button.
3. Click chosen service on extension's Share Tab.

Personalization (settings):
On Share Tab you can sort services to fit your preferences by dragging the service up or down.
On Settings Tab you can manage which services should appear on Share Tab (up to 11 services) and reset Share Tab to default settings.

NOTE:
After installing the extension you will need to reload already opened tabs in order to use the extension with them due to known Opera bug.