I'm generally not a fan of web-embedded widgets, because very seldom do they actually save time or significantly improve the experience of enjoying a page's content in a way that compensates me for the extra memory usage. Exceptions to this, in my opinion, are some video players (at least the one that play videos longer than 12 seconds), and embedded PDF documents.
There may be other isolated cases where widgets genuinely improve the browsing experience, but in the case of these two widget types, they're genuinely saving time. Downloading a video file is pretty time intensive on most connections, and downloading and viewing a PDF, at least on my lame machines, can take several minutes for Adobe Reader to load.
Enter Docstoc. I've always been a fan of their service, and they've announced a few updates to their to their PDF widget product tonight. Former Mashable writer and current Social Media Manager at DocStoc Sean Percival dropped me a line this evening to let me know what they've got cooking:
We've got an update that lets the owner of private docs on DocStoc see who has viewed, downloaded, and emailed their documents. The document guestbook helps track document views you share your private document link. The new features allow document owners to protect their files by limiting recipients to view (but not download) their private documents, taking away the headaches of large email attachments and concern if the recipient actually received the file.
It's a great set of features that really improve the attractiveness of the system over some of the alternatives in the space.