Generally speaking, I won't invest in something without doing at least a "token" amount of research, pardon the pun. Ideally, I like to UNDERSTAND what the heck they are trying do with their coin or token before I buy in. And most of these things have fancy web sites and lots of big words, but I usually come away having no idea what they actually intend to accomplish.
So I've only participated in 3 so far (Exscudo, Encryptotel, and Peerplays). Oh I also bought into the Storj crowdsale, but only because I intended to top off my SJCX holdings anyway, and the crowdsale was cheaper. I prefer passive investing, not a day trader. So I'm ok with my new crowdsale STORJ tokens being locked up for a bit.
Other than the individual coin/token home pages themselves, here are the sites I like to visit to read up on current and future ICO's and Crowdsales:
https://www.smithandcrown.com/
They focus mainly on Tokens but also review standalone blockchain coins as well. Their reviews seem to be original and thorough and generally provide good information and links to help you figure out what the heck these things are. And if they are worthwhile.
http://icorating.com/
Lots of things here! Tabs for Future and Ongoing, as well as Past. The reviews aren't as thorough, looks like mostly just regurgitating the company lines. But it's nice seeing everything all in one place and you can burn an afternoon going through it all if you are so inclined.
https://www.coinschedule.com/
Their claim is that they "only list the projects worth following and investing". So if you are lazy and want to trust them, they have narrowed things down a bit.
Again, these are just resources, please make your own, informed decisions. The above may all be in bed with various coins and tokens they are "reviewing" for all I know.
And if you know of any good web sites for researching this stuff, please comment and let me know!