I am pretty sure most of you already know at least the concept of couchsurfing. The website basically brings together people with an extra spot in their flat and people, who travel on a tight budget.
Obviously there are other motivators behind using it, such as wanting to learn a language, meeting new people and having a local guide. You experience with your host might vary from meeting your new best friend to basically not seeing them for more than for a few minutes at night.
Just like a bunch of other girls I had always loved and admired the idea behind couchsurfing  but was too afraid to try it out myself, especially when traveling alone. But when I was in Chile through a mutual friend I met José, an incredibly nice Chilean, offering a spare room in his flat in central Santiago to strangers. As my time as a horse back riding teacher was running out and he seemed like a great person I decided to stay with him.
And what a wonderful decision that was. José and I had an amazing time, we traveled together, we partied together and he showed me a lot of beautiful spots in Santiago I would probably not have seen otherwise.

I also got to experience the awesome community that makes up couchsurfing, as José was hanging out with a few other couchsurfers. One of these lovely people, Luiz from Brasil lives in Madrid now and I will visit him this july.
You might say, well these were not strangers and you did not find them via the actual website. And yes you are right, this was more of a mutual friend situation. 
During my trip to Brasil I had my first "real" couchsurf experience, staying with a nice Brazilian lady and her mom in Niteroi, outside of Rio. While this was more about having a place to sleep, it was still really nice to see Niteroi, a place I as a tourist would normally never have gone and taste the delicious Brazilian breakfast the lovely mom of our host made.
This summer I have found a couchsurfing spot in Paris and I am looking forward to see how that will work out.
In general I can only see pros in using couchsurfing. Next to everything I mentioned before it is just wonderful to see that people all over the world are so interested in meeting new people and learning about new cultures, that they offer their home for free. 
Of course you have to be save, I recommend looking for hosts with a lot of reviews and experience. Also it is obviously more work to find a host, than to find a hostel or hotel. Reading the profile of your host very carefully and also having an interesting profile yourself is crucial. The homes of your host may not always be super central and you might get a lot of rejections before you get a spot.
But for me so far it really was worth it, you have a safe place for all of your stuff (unlike a hostel), you get insider tips, meet great people and last but not least save quite a large amount of money.
I can also recommend sending out an open couch request and not only write them to certain people yourself. People will offer your homes to you! How cool is that?
Have and of you guys done couchsurfing? What did you think?