Wikipedia style site
  Develop a site similar to a wiki in which one can create, edit, and view various articles.
    Take it a step further and allow pages to hold images.

Imgur Style Site
  Develop a site similar to imgur, an image hosting platform, that allows a user to upload a photo and access that photo with a unique URL.
    Take it a step further and add a basic front-page that shows the latest uploaded images

Pastebin Style Site
  Develop a site similar to pastebin in which a user may paste any text into a pad, and save it generating a unique URL that will give anyone access to the pasted text.
    Take it a step further and allow collaboration. Nothing automatic like google doc, but rather refresh to see the changes.

IRC Style Site
  Develop a site that mimics an IRC of sorts. Allow for nicknames, and rooms. Save the conversations, so when someone re-enters the room, it'll show the previous messages they had missed.
    Take it a step further and add room moderation and commands for specific users. Create roles to decide who can use what commands. This will require accounts.

/** UNSURE IF SOFTWARE IS FINE AND NOT JUST SITES **/
Gyazo / Screen Image Capture Program
  Develop a program that will screencap your desktop on a given hotkey and either save to disk or upload to an image hosting site such as imgur.
    Take it a step further and put the program in your windows task tray, or allow for basic image manipulation like scaling or cropping.