Flickr Gallery Plus!
Flickr Gallery Plus! is an extension/a Greasemonkey userscript, offering you:
- View one large picture with the other thumbnails in the set next to it.
- Click-selection of whichever picture you want to see larger.
- Keyboard navigation with left and right arrow keys to go back and forth amongst pictures.
- View a slideshow of all pictures in the set.
Firefox extension
Greasemonkey userscript prerequisites
Firefox 
First, install Greasemonkey. Then, just install the Greasemonkey userscript provided in the Downloads section., and you're good to go!
Safari GreaseKit userscript 
Start with installing GreaseKit. Then, just install the Greasemonkey userscript provided in the Downloads section. All set!
Google Chrome 
First, follow the instructions in HOW TO: Install Google Chrome Greasemonkey Scripts (Windows Only).
Then, just download the Greasemonkey userscript provided in the Downloads section, and place it in the C:\scripts folder, as described in the linked article above.
Opera userscript 
First, just download the Greasemonkey userscript provided in the Downloads section.
Then, what you need to make it work is just to add a folder to your Preferences where Opera should look for custom scripts. Go to Preferences > Advanced > Content > JavaScript options, and choose a suitable location. This process is described more in detail in Opera: Tutorial - User Javascript.
