One of the scourges of e-mail is file attachments, and particularly those from people sending files made by their new word-processor or presentation programme that half the people receiving it can't open. While proprietary software vendors love this errant behaviour (it keeps up the pressure for people to re-purchase software they don't really need so they can read other people's work - AKA "upgrades"), it's really anti-social behaviour.
To start with, most of us don't need the source file for a document or presentation. Usually we just want to read it or review it. Then many of us have mobile devices which may not support the file format you are using. Finally, if we actually do need to collaborate, it would be better to use a collaborative editor than to circulate files and then have the problem of dealing with all the different ways people can comment on them afterwards
For the vast majority of us, a document we can read is sufficient. A PDF, for example - the name itself tells the story, "Portable Document Format". While it was started by Adobe many years ago, today PDF is a standard and there are many ways to read PDF files. Even better, most smartphones and tablets can read PDFs out-of-the-box.
So if you have to send a document attachment, please please please send a PDF so the rest of us can read it. If the file isn't confidential, you might even put it into a "locker" on the internet - say on DropBox - and let people collect the file from there. But make sure that's a PDF too, please, and remember mobile devices may not easily be able to access it!
Portable But Editable
Of course, some people will need to edit the document you are sending. Did you know you can send a final document as a PDF attachment that everyone will be able to open and view, but which people who need to will also be able to open and edit?
The document that can do this magic is called a "Hybrid PDF", and anyone can make one using open source software. LibreOffice (and related packages like OpenOffice.org) have been able to make these editable PDFs for quite some time. A Hybrid PDF is a normal PDF file that any PDF reader can display, but with the added benefit that the original source document is also embedded in the file. Any suitably advanced office suite, such as LibreOffice, is able to retrieve the source and allow you to edit it.
To show how they work, I have prepared a PDF that provides instructions on how to create a hybrid PDF with LibreOffice. Feel free to download it and take a look at the instructions. Naturally, the PDF is itself a hybrid, so try dragging and dropping it onto your office suite and see if it can be opened. If not - well, you need to get a modern, innovative office suite instead of the one you're using! It also works for presentations - I've prepared a sample presentation about OSI for you to try.
If you like this idea, send the file to your colleagues and friends and tell them all attachments from you in future will be these editable PDFs. Let's start a wave of change!