In the early days of Bitcoin, it was easy to get your digital paws on some of the virtual currency. Evangelists everywhere were willing to just give out what was then an insignificant amount of bitcoins. As the value of bitcoins relative to the price of fiat currencies has risen, people have become more stingy with their bitcoins. What was worthless is now valuable and the sources for free bitcoin have seemingly dried up.
But they haven't completely. There are a few services out there keeping the tradition of free bitcoin alive. Mining costs more than it is worth, but faucets still exist, even if they drop an insignificant amount of bitcoin. Faucets are services that will give you some free, but an insignificant amount of, bitcoin.
It is hard to say that faucets are worth the time, but if you absolutely must get some bitcoins and you absolutely can't pay for them, faucets will get you free bitcoins.
Each faucet will only pay out every 30 minutes to 24 hours, and will only include 30 – 500 Satoshis (each Satoshi is a millionth of a Bitcoin). That small of a transaction would have trouble getting through the blockchain because miners would likely find the potential for a reward too low. The workaround is to have several faucets point their bitcoins at one “Micro-transaction Wallet” that works off the blockchain. Once enough satoshis are acquired, the service will transfer the BTC to the wallet of your choice.
Two popular choices that I have tested are CoinBox and BitChest (A third service, Microwallet.org also exists but users have been complaining about suspicious faucet sites.) Both of them have a decent number of faucets but I was particularly impressed with BitChest.
BitChest gathers its supported faucets within its own Dashboard, shows how much each of them are paying out and how long you have to wait before you can use them again. I also found it to be a quicker earner than CoinBox, earning over 1500 Satoshis in my first run through the faucets compared to less than 500 Satoshis for CoinBox.
A much quicker way to earn bitcoins simply by clicking is to use CoinWorker, which will have you completing mundane tasks like grading search engine results for a small amount of bitcoin. You can get paid in a much higher equivalent amount of money in fiat at some similar services, but it is at least possible to earn a few dollars an hour in bitcoin using the site.
Either way, that isn't a lot of money, and it will likely be a while before you can pay out. If you are the lucky sort however, you could try increasing your free bitcoins on the various Bitcoin gambling sites out there.
There are dozens of virtual bitcoin casinos, and most of them let you start with a small amount of bitcoin and bet even smaller amounts. Since everything is based off of math, they can allow you to bet much smaller amounts than fiat gambling sites allow, and payouts can be similarly small.
The Bitcoin Wiki has a more complete list, but a few reputable ones include SatoshiBet.com and SatoshiDice.com although SatoshiDice is no longer available to U.S. users.
There is also one decentralized Casino out there, which runs on a new coin built on the Bitcoin blockchain, Chancecoin. Chancecoin allows users to play as either a gambler or the house, with house players getting a 1 % edge.
Sports betting is also another way to increase (or completely loose) your bitcoins. Betmoose allows you to make or take a bet in a p2p system on just about anything, so long as you can find someone willing to bet against you.
Bitbook.ie is a great sports bookie that pays out automatically and has reliable odds for every game. Several Casinos also offer a referral program. If you know anyone who is likely to drop some bitcoins through gambling, you could get a cut of that action. Check to see if your favorite Casino has a referral program.
It is also possible to gather some bitcoins from the community. Both Bitcointalk.org and the /r/Bitcoin subreddit can be a source of Bitcoins. But, people also don't like it when you ask for them. Rather, participating in the community will ultimately result in someone giving you bitcoins, so long as you have something valuable to add to the conversation.
Your signature at Bitcointalk.org can also be a valuable source of income. Several companies will pay you to post on the forum with their site in your signature. You'll have to have a certain post count, but it is a fun way to participate in the community while earning some Bitcoins.
If you are a student, you might already be entitled to some free Bitcoins. MIT's USD $100 for every undergrad program is already known, but there is a way for nearly every U.S. student to get free bitcoins. Students who sign up for a new account at Coinbase with a .edu email address will get USD $10 worth of free bitcoin. Students can also get USD $1 for referring other students from their school to the service. So far, over 20,000 students have taken advantage of the promotion.
Bitcoin is ultimately a currency, so getting some bitcoin through selling a product or a service is one of the most natural ways to obtain the currency. Etsy, an eBay-like site for homemade goods allows sellers to accept payment in Bitcoin and gives you access to a huge market of buyers (unfortunately, most of them are unlikely to use Bitcoin). CryptoThrift is the internet's biggest Bitcoin-fueled alternative to eBay and lets you purchase and sell items for either Bitcoin or Litecoin.
Fiverr lets people post or offer jobs for the universal price of five U.S. dollars. They now allow their freelancers to accept payment in Bitcoin. It may only be five dollars, but that is still a quicker way to earn some bits than using a faucet.
For more serious jobs, there are a few Bitcoin paying gigs on freelancer.com and many more on Coinality, a Bitcoin job board.
It isn't quite “free” bitcoins, but by selling something unwanted items or performing a service, it is possible to obtain some Bitcoins without ever investing any fiat currencies.
Internet marketing is big business right now, and it lends itself well to Bitcoin. Simply linking to content you think people will be interested in using a URL shorter that throws in a few ads can net you some cash. Why not bitcoin? Coinurl works like AdFly and similar services, only it pays out in Bitcoin. It isn't the most satisfying way to make a living, but it remains a viable way to pick up some free bitcoins.
Is it possible to get bitcoins without spending a dime? Sure, but you may have to work for it.