Everyone has a platform for free, public expression. For Banksy, it's the streets. For me, it's my blog.
Before the Internet, none of us had a megaphone. We all had to be signed professionals in order to get a deal for distribution. But that model is broken; my work can be found just as easily as the famous musician, artist, and writer.
The difference between amafessionals and professionals is in the marketing. Sometimes you need the backing of a bank to help spread of mouth. For instance, I can blog and tweet all day but a legitimate writer gets an interview with the New York Times or CNBC and their shit blows up.
We can all make stuff but it's the quality of the network that separates the bedroom creators versus the signed artists.
In the meantime, use your anonymity, the tech tools, and free Internet distribution to practice. There's no excuse but to create something, even if you're never found.