If you don't want to install bitmessage, you can register on http://www.bitmessage.ch/ and use your email. Once registered there, you can write an email to BM-2cXdbRBsBWXmdTqsN2s3jd28cpEunJX6Ek@bitmessage.ch (or BM-2cXdbRBsBWXmdTqsN2s3jd28cpEunJX6Ek@bitmailendavkbec.onion if you want to access through TOR). The only limit is that you can't subscribe to Bitcoin Galore address and receive automatic round reports.