Stop Killing Time
StumbleUpon came and went. Time-wasting websites and apps are on par with logo-emblazoned pens. There may have been a period in the early 2000s where people wanted to use the internet just for the sake of using it, but that’s over. People are super busy now, so give them something that makes their life easier rather than killing time.

You won’t “go viral”
Unless your brand is already a breakout success, it’s very unlikely anything you create is going to go viral without any paid advertising. Fun fact: almost every branded viral video on YouTube’s home page got about 1/3 of its views from paid advertising in the first 6 months. The same is true for Kickstarter or IndieGoGo campaigns: if you don’t raise 1/3 of the money from friends and family, or pay for Google Adwords, you’re very unlikely to raise any money at all. Things like gamification work, but you have to be subtle and work really hard.

You’re (still) designing websites like print
Websites are not the digital equivalent of paper brochures. They have a tremendous amount of versatility and should not be treated the same. A website doesn’t need a table of contents (navigation with 25 options); instead it needs you to architect the user’s flow throughout the environment. You need to design an experience, not just provide information. When people visit the site, it doesn’t matter if they read all the information, it matters if you blow their minds.