Free Power Pivot! 
Make Power Pivot freely available in all editions of Microsoft Office/Excel 2013/365 and beyond.

Power Pivot was a free add-in for Excel 2010 and "the best thing to happen to Excel in 20 years" (words of Mr. Excel - Bill Jelen). Unfortunately with Office/Excel 2013 and Office 365 Power Pivot has been mired in endless confusion around determining when you have it when you don't :-(

Just read these posts and the comments on those pages
> Office 2013, Office 365 Editions and BI Features (does it need to be this complicated?)
> Mr Excel (Bill Jelen)'s lament about slow adoption of Power Pivot
> “Hey, Who Moved My (PowerPivot 2013) Cheese?” (297 Responses and counting. Ignore the Update at top of this post: having Power Pivot available in Excel 2013 is a minor victory and does not solve the core issue)

Here are some of the recent comments:-

Sep 30, 2014
Gene says: Terrible idea, Microsoft! I am an instructor at a community college. Our text teaches students how to use PowerPivot. We have a bulk license agreement for Office Professional. If “Professionals” can’t use the PowerPivot, there is a problem. Also, there is a big push out there to get people certified in using Excel. What is a certification worth if using PowerPivot can’t be a part of that?

Sep 15, 2014
Cameron says: Just want to add my voice to the many people above about this. Same story on my end – I have Office 2010 on our work computers, used PowerPivot and fell in love, saw a post on PowerView and ran a small scale test on a computer off the network to ensure Excel 2013 worked well with our data sets.
Worked great on the test computer so I enthusiastically ordered a copy of Home & Student 2013. After not working, finally made it to this post – needless to say, I couldn’t submit my refund application quickly enough.

Very disappointed in Microsoft…

Sep 9, 2014
Han says: Just bought Office 365 and to my horror, realized that there is no PowerPivot support for excel and came into this post. Really, Microsoft? Seriously what are you thinking…

It even makes business sense for Microsoft

There are estimated to be 500-750 Million Excel Users. Imagine if all of them, okay even a small percentage of them upgraded to using Excel with Power Pivot. Their impact would be multiplied 10x-50x right away and they would lead the next wave of BI revolution within their organizations. Sounds farfetched? Here is my true story and the story of many other Excel users who have adopted Power Pivot. Of course at some point they would need to use and can be sold one of the Servers or Cloud Services (SSAS, SharePoint, Power  BI).

Power Pivot is a great way to strenghten Microsoft's position in the Productivity space and make bold new inroads in the BI space without even trying to take on the entrenched players. 

Play to your strengths Microsoft and free Power Pivot!