After seeing disappearance of thousands of my old photos that I have been uploading since 2003 at the flickr site and could not be found on 'archives' section, I contacted the flickr team. This is how they responded:
On 6/30/06, Flickr Support <email@example.com> wrote:
You will have to delete your newer photos or upgrade to Pro
in order to recover your older, hidden photos.
If you are a huge flickr fan and have similar difficulties in accessing older photos just because you have not switched to pro subscription, this simple trick might help you. I am not sure any of the leading hack-sites like Life Hacker have published similar description.
First of all, go to Flickrleach or Flickrgrab (that site looks like a mirror of Flickrleech). Select 'By Username' if you have been using flickr before yahoo takeover. Or else select 'By User ID'. Type your User name (old users) or User ID (Yahoo ID won't work. You have to copy-paste the URL address of your flickr page). Now click 'Go'.
Now that you can see all of your photos no matter when you have uploaded, as shown in the photo below Permalink is here.
Now, select all photos by mouse. Be aware if you are a heavy flickr user, you will have thousands of photos and flickr leach too will have many pages (each page having 200 photos).
Now, drop these photos to your html editor like MS Frontpage or Dreamweaver, as shown below (in this case, MS Frontpage).
Now publish it if you like (have a look at my photostream), or just keep it by yourself as a secure archive of your whole flickr photos!
This method has only one draw-back. If you have some hidden photos in flickr that you would like to archive, flickrleach cant help to grab them. Any out sights on this issue are welcome.
PS: Some one might think why you need to do all these, depending flickrleach would be just simple to see your hidden photos. But no one knows when yahoo/flickr is going to change it's API policies such that flickr leach can no longer grab them. But yahoo cant change the URL address of your old photos or delete them, by breaching their promise gave to us years ago.
Lately I give a try at google's picasaweb and I found it impressive. Total upload limit for free users is currently 1GB and that obviously matters, but ability to make as many albums as you want is a plus point (in flickr, albums or so called 'sets' are limited only up to 3 for free users).