The Katawa Shoujo Walkthrough (guide to different routes / stories of good and bad endings ) that I am writing is also posted on the link above. ^ I also plan to make a Katawa Shoujo scene flowchart, even though I know there are flowcharts made by others already existing.
About the game / visual novel, from its official website:
Katawa Shoujo is a bishoujo-style visual novel set in the fictional Yamaku High School for disabled children, located somewhere in modern Japan. Hisao Nakai, a normal boy living a normal life, has his life turned upside down when a congenital heart defect forces him to move to a new school after a long hospitalization. Despite his difficulties, Hisao is able to find friends—and perhaps love, if he plays his cards right. There are five main paths corresponding to the 5 main female characters, each path following the storyline pertaining to that character.
The story is told through the perspective of the main character, using a first person narrative. The game uses a traditional text and sprite-based visual novel model with an ADV text box.
Katawa Shoujo contains adult material, and was created using the Ren’Py scripting system. It is the product of an international team of amateur developers, and is available free of charge under the Creative Commons BY-NC-ND License.
Unlike other visual novels especially popular ones (Clannad, Kanon, Little Busters), Katawa Shoujo is a visual novel developed by a community (Four Leaf Studios), and is released to the public for free. It’s not suitable for all ages though because of adult scenes, but I believe that adult scenes may be turned off if the player prefers not to see them.
Update (Feb. 7, 2012): I’ve been enjoying Katawa Shoujo. I have two remaining stories left – Rin and Emi’s. I’m trying to get all endings – good, bad, and neutral if there’s any. But not all adult material is blocked when you choose the game to disable adult content. The main adult scenes of Katawa Shoujo are hidden with photos – hamster, foods, etc…, but scenes where the female characters are without clothes are still shown. So, Katawa Shoujo is still not safe for younger players and for work, inspite having a “disable adult content” option.