I post under my real name in the community forums I frequent, but I also create smurf accounts (throwaways) for when I want to say something that could potentially harm my reputation in the future. It is important that there should be at least the option of posting anonymously - it eliminates the inhibitions that you would normally have, so you can really bear your soul. That might be uncomfortable for some readers - especially if they consider the words or ideas "offensive" - but that it is valuable to know what people are REALLY thinking, rather than self-censored version.