Picasaput is just another picasa web album uploader for linux-like systems. This picasaput.tar.gz package includes the java class file and the source code.
Install and Usage
Download picasaput.tar.gz package. Extract that file, and create a symbolic link:
$ cd ~/lib
$ tar xzf /path/to/picasaput.tar.gz
$ cd ../bin
$ ln -s ../lib/picasaput/picasaput picasaput
To upload photos, just run
$ picasaput /dir/to/images/*.jpg
Finally, modify the default (empty) account to your Google Account is a smart idea.
Source Code
Picasaput.java is the only source file. This version works under JRE 1.4+. And there are lots of codes are stolen from GData Java Client Library.