Many sites that offer free services require users to create accounts. Registration is free so you think: "What's the harm?" Well, there is no harm, unless you find an inbox full of spam from that company to be a nuisance.
Some websites have even simplified the free registration process by giving you the option to register with your Facebook account. But maybe you don't want a service you've used one time to have access to your email address, friends list, birthdate, and various other forms of information from your Facebook profile.
Instead of avoiding these "free registration" sites altogether, you can try BugMeNot.com. It's a free website that provides usernames and passwords so that you can complete the free registration without giving them your personal information.
Fun Fact: Guy King, the man who started BugMeNot, is also behind RetailMeNot. It's a site that provides coupons and promo codes for online stores.
Simply go to the site and type in the name of a website you'd like to access that requires a free registration. If login credentials for that site are available, a list of username/password combinations will appear on the screen. It even tells you the success rate of those credentials and you can check off whether or not they work for you as a tip for future users.
If login credentials for that site are unavailable, it may be because that site is blocked. Some sites are blocked because the registration isn't free, like a Netflix subscription. Some sites are blocked if there's a risk of fraud because those accounts hold banking information, like Amazon. Some community sites are blocked if users must register to add content to the site, like Reddit. Websites that don't want to be a part of the BugMeNot database can petition for removal if they fit one of the three scenarios mentioned above.
However, login credentials may be unavailable simply because no one has needed them yet for the particular site you're trying to access! BugMeNot allows you to register a fake account for free registration so that you don't get spam. Then you can share these credentials with future users.
So if you want to avoid spam but still reap the benefits of sites that require registration, then BugMeNot is a workaround you should consider!