Microsoft's Office Web Apps are great for those with a SkyDrive account and any device with an IE, Firefox, Chrome or Safari browser who don't want to lug the full Office 365 suite around. Since functionality can be a tad limited, however, Redmond's just added more features with the latest update. For starters, you can now copy and paste pictures from the web into Word, PowerPoint and OneNote Web Apps. Other new functions include cursor-following tools in all the programs, the ability to rearrange slides in PowerPoint Web App along with comment viewing, touch-based chart resizing and more in Excel Web App. Microsoft's posted some sample files that work without a SkyDrive account, so if you want to give it a whirl, hit the source.
Source:Office Web Apps