The overall cost of hosting is trivial compared to the cost of managing the site - systems administration and community management.
Somersoft (along with some of my other sites) currently utilises two Linodes - an 8GB database server and a 4GB web/app server. We had plans to add a third search engine server running ElasticSearch, which would probably be a minimum of 4GB as well.
However, the hosting is only one component of the systems required to operate a busy site like this:
- Database hosting US$80 per month + $20 per month for VPS backups
- Web/app server hosting US$40 per month + $10 per month for VPS backups
- Performance monitoring (Linode Longview) for these servers US$40 per month
- Amazon S3 storage for website backup data approx US$10 per month
- Code Deployment (DeployHQ) approx US$20 per month
- Anti-spam (Akismet) US$45 per month
- Forum software: approx US$25 per month
- Helpdesk software (HelpSpot): approx US$20 per month
- Email deliverability (Mandrill): approx US$5 per month
- GeoIP IP address geolocation web service (Maxmind): approx US$5 per month
- System monitoring and alerting (Pingdom): approx US$15 per month
Total approx: US$335 per month = $4,020 per year = approximately AU$5,200 per year (I liked it so much better when we had a high AUD!!!).
Also - don't forget that these are unmanaged servers, so I have to do all system administration work as well - I would easily spend four or five hours per month just maintaining the servers, sometimes much more.
Just by comparison of how (relatively) cheap hosting is these days - I recall an early version of Somersoft (around 2002 or so) we hosted on a NetRegistry server which was costing Ian $1000 per month. It wasn't long after this that we found a much cheaper hosting solution (Quadrahosting), which we used for many years until we eventually outgrew their servers and needed to move to a VPS solution.