Since OP is asking for "crypto projects" in general let's not limit ourselves to only ICOs and Scamcoins since even crypto exchanges and scam cloudmining sites can also be counted as one. Last year we all have heard about QudrigaCX and their users' misfortune brought to by the death of their owner who took the keys for the exchange's cold wallet with him, the news about him and their exchange went viral pretty quickly since we are talking about millions of dollars which is unrecoverable. Cloudmining sites that also made an exit scam made it into the headlines like how Hashocean suddenly disappeared without a trace, they stole a lot of money from their users as well. When we are talking about them going viral I agree to what others have said, you'll create more noise doing bad rather than good publicity for their project.
Great that you remembered hashocean, I wanted to write it. This was the most popular cloud mining website in 2016 and they stole millions of dollars, as I remember their scam leave affected bitcoin's price.
I want to include another very interesting and old projects:
1. Bitcoin Savings and Trust <-- it was ponzi scheme operated by Trendon Shavers.
2. Btc-E (Hack at first and then you know what happened finally).
3. Bitmixer <-- yeah, this website was super money making machine and quickly become viral but owner had to shut down it (no one was scammed).
On another hand viral projects are Bitpay, Binance and all of current widely used bitcoin related websites. But it was mentioned correctly, more noise is caused by hacks, scams and etc.
You can see projects that went viral and then got hacked/scam there:
https://bitcointalk.org/index.php?topic=83794.0