Box.Net widget enables to share large files with others and use storage at Box.net server. To enable it one need to find the “Box.net file sharing” widget in widget tab of their blog and drag it to sidebar and click on it to open.
If one has already a Box.net embed code post it into the text box. If you need a code, click the “go get some HTML code” link and paste the resulting embed code into the text box. Then pick a size for your widget and save it.