There are so many different components to Flickr. I still think this is one of the coolest sites ever!
Now with the third party sites included-Goodness! It's like that old movie about the lady with schizophrenia, with Joanne Woodward's character as "The Three Faces of Eve" versus the multiple personality disorder in which Sally Field played the 16-separate-personality-patient, "Sybil." Everytime you think you know her, she presents another personality.
So, you think you know what Flickr is all about, but, you probably only think you know. The third-party programs present everything you only thought you knew but were afraid to ask. You can play games, choose different fonts and background colors, present slide shows, display personal photos (as well as upload them, or post them on your own blog site). You can use Invitr to display your personal photos to only one person, or as many people as you like. Using Organizr, you can organize your photos using tags, titles, dates, places, etc. and really be as systematic as you like. And the best part is--you don't need any softwear to do a multitude of tasks!