I'm not familiar with SlideShare, but from Wikipedia that seems to focus on sharing presentations rather than building them.
Here's what I mean, specifically: advisory work done by the big consulting companies and Wall Street M&A shops usually consists of lots and lots of Excel files being carefully massaged to create certain outputs that are then dropped in as images into PowerPoint with some text around them, mostly following the exact same formatting guidelines, which are then printed, bound and shown to clients.
Currently, you have to train people to not only know how to come up with the data (i.e. corporate finance, accounting, management consulting) but also teach them how to use powerpoint, think about formatting, make sure they memorize the right color palette, etc. Sometimes formatting alone is 50% of the work – your boss will always tell "you used the wrong shade of blue"...
A lot of these pages are the exact same across assignments. One example is a standard page with valuation multiples over time, comparing client company against a set of peers and/or the S&P500. Or a stock price performance chart.
Annoyingly, you have to set up pages manually virtually every time, and there's no separation between presentation and content.
With RMarkdown + RStudio, you can write Markdown code and embed images into your resulting PDF. Banking / Consulting is doing the same thing, except using PowerPoint. But PowerPoint is a slideshow app, not a PDF authoring tool.
My hypothesis: creating a PDF authoring tool that embeds data from Excel / other sources with formatting kept separate (think a separate CSS file) would be a game changer and revolutionize the industry (though admittedly Wall Street hates changes and convincing people to use this would be an uphill battle)