AutoDesk (The company mainly known for AutoCAD, 3ds Max, and Maya) made a web based application strictly for architecture, and it's called HomeStyler, now it's pretty nice, and powerful, however you must have Flash installed in order to use this, cause it is a flash based web application, however this is a great way for users to get started/introduced to architecture using AutoDesk's new web application HomeStyler.

(Seeing as how I found this about 2 or 3 weeks ago, and finally have a few minutes to spare online, so I thought I'd share this with you guys)

Wow i could play with that all day
I love the way you can alter each piece with nodes like paths or vector editing.