May I take it that you are hosting this yourself Dan? Surely it can't be too expensive to have it professionally hosted?
Christ no! You couldn't get the connection speeds we need across the network on a domestic line. Upload speeds are shocking even if you have 150MB/sec download lol
We're hosted in France on Teir 3 backbone (faster than what we get in the UK) and use a server management firm based in Italy, who are experienced in small-business DDoS attack prevention and monitoring. As we've had a bit of that in the past. And we use a range of software and hardware based all around the globe to ensure we stay online.
Problem is, we have one SSD that we load content from, and no slave (it wouldnt work the way we are setup) so when that fails, it's end of posting!
We've managed to load from it, and have cut back on cron jobs, taken backups offsite, done a few other tricks.
Our hosting costs in the region of £450 per month per domain! Hence me shutting down the 22 or so forums that I hosted but didn't use and nobody visited much lol
We couldn't host on cheap hosting. We'd never be online.