You may download the Picasa Zenfolio upload button from this page. This allows you to upload photos directly from picasa to Zenfolio. The Zenfolio website can be used sell your photos or you can simply provide an aretful gallery. You must have a Zenfolio account prior to using the upload button. If you like the software please consider making a donation.
Click this link to add the software to picasa
No big secret here, picasa allows you to add a button to its interface.
This button can point to a url, which picasa will then open in its mini browser,
along with opening the browser picasa all posts an RSS feed of all the pictures selected.
So the button (you installed by clicking the link above) posts the information back to this server. I then authenticate using Zenfolio's API and retrieve the list of galleries the images can go into. I allow the user to select the image size to upload and then the post the information. Picasa does some magic and sends all the selected photos at the resolution specified to my server. I receive the posted pictures and translate that information to something that can be sent to Zenfolio. I then tell picasa to open the results page where I display the photos that I receieved along with the uploaded status and a link to view them in the gallery you choose to upload them into.
I am not responsible for any loss or corruption of data.