I use an application from Afinion called "Project on Web Viewer"
(
http://www.afinion.com/). This application works exteremely well for us as
we recieve MPP files quite often and need to view them and/or print them
out. However, we do not have the need to manipulate or create our own MPP
files so owning MS Project is not really necessary. Unlike other viewers,
Project on Web Viewer reads the native MPP file so there is no need for the
creator of the MPP file to convert it to another format. While it is not a
free viewer, Project on Web Viewer has met my needs quite well and is very
cost effective (it is better then shelling out the total cost of a full MS
Project license). I would highly recommend it. I hope this helps. Post
back if you have other questions.