The disadvantages to consider with viral marketing include the nuisance factor. Due to the large amount of email people receive daily, viral marketing messages may be viewed as spam. Another consideration is negative marketing buzz. A message may not be construed as intended, and could be discussed in a negative manner. Viral marketing can also be hard to measure. 

I enjoy how you lay out real numbers. A lot of people wouldn’t do that. While you admit that you are somewhat conservative, I think the $1M in CD’s is just too conservative. Assuming you don’t need the cash flow now (which you say you just save anyways) then all that could be invested for potentially higher returns. For example, what if you bought San Francisco real estate along the way instead of CD’s. Or, an SP500 Index fund. I bet your average return would have been higher than 3.75%. Sure you could lose it, but the point is if you don’t need the cash flow now, you should try to increase that nut as high as possible until the day you actually need it. Your nut could be $5M right now if you had invested in asset classes other than CD’s for the last 14 years. Don’t get me wrong, you have done far better than me, but I guess I would take a little more risk if you don’t rely on that cash flow.
What I did: I first identified my favorite places in the world to live: San Francisco, Honolulu, Paris, Amsterdam, New York City, and Lake Tahoe. I then looked up the median rent and housing prices for each city. Then I factored in private education costs for two kids to be conservative given I may not have two kids and public schools are often good enough. After calculating all vital costs, I then did a self-assessment of how happy I was making $50,000, $100,000, $150,000, $200,000, $250,000, $350,000, $500,000, and $750,000. I decided working 20 hours a week making $200,000 a year is the best income balance for maximum happiness. 
Index funds provide you with a way to invest in the stock market that is completely passive. For example, if you invest money in an index fund that is based on the S&P 500 Index, you will be invested in the general market, without having to concern yourself with choosing investments, rebalancing your portfolio, or knowing when to sell or buy individual companies. All that will be handled by the fund which will base the fund portfolio on the makeup of the underlying index.

To your point about Municipal Bonds, my concern is tax reform. While everything is mostly being worked behind closed doors (and likely wont ever see the light of day). There is still the chance they propose to limit the amount of the tax free nature of these bonds. While I dont sen panic in the streets, I do see a scenario where bond prices get additional pressure because municipalities have to increase rates due to people putting their money to work elsewhere.
Haha, that is too funny. I wanted to make an app back in the day called “MyShares” (You can probably tell how I cam up with the name at the time). The idea was that I would loan out books and DVD’s and then would never get them back. Then I thought, how cool would it be if I could rent those items out and that would motivate people to bring them back. Obviously, books and DVD’s are cheap, so this isn’t the money maker. The idea that would probably make the most money would be things like tools, ATVs, etc.

Another benefit of investing in rental properties is the loan pay down. If you obtain a loan to buy the property, each month your tenants are paying off part of the loan. Once the mortgage on the property has been paid off, your cash flow will increase dramatically, allowing your mediocre investment to skyrocket into a full-fledged retirement program.
The term viral strategy was first used in marketing in 1995, in a pre-digital marketing era, by a strategy team at Chiat/Day advertising in LA (now TBWA LA) for the launch of the first PlayStation for Sony Computer Entertainment. Born from a need to combat huge target cynicism the insight was that people reject things pushed at them but seek out things that elude them. Chiat/Day created a 'stealth' campaign to go after influencers/opinion leaders, using street teams for the first time in brand marketing and layered an intricate omni-channel web of info and intrigue. Insiders picked up on it and spread the word. Within 6 months PlayStation was number one in its category—Sony's most successful launch in history.
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