Picasa

Is a free programe wich allows you to share pictures with people using your google count ( Picassa belongs to Google since 2004). Picasa allows you to make adjustments in a practical and simple way, only toching some parameters you can get very good results.

You can make collages in seconds, only selecting the pictures, picasa make a collage randomly for you, then you can improve it.

http://picasa.google.com/