Because file-conversion is always exciting, and because I found this obscure little tip buried way down in a forum thread — but it’s golden — I figured it needs to be published more plainly:
When you need to open an Apple Pages document but you don’t have the Pages application itself, try this, regardless of your platform (Mac, Windows, Linux, whatever):
Pages file[s] (all iWork files actually) are [in fact] .zip archives. Change the extension from .pages to .zip and you can unarchive the file. One of files remaining will be a PDF of the formatted file.
— mysterytramp, originally here