[jjice]

While I think a $5 VPS is under kill for something like HN due to the traffic, that actually sounds like a fun challenge. Especially if you don't show point values, you can cache the majority of the page (everything but the username and points) until a new comment is made. That would require only doing a query and template completion once per comment, which is probably tiny compared to the number of reads. I imagine that if you had an extra GB of ram for Redis, you'd be in a great spot.

Sounds like a fun hackday to me.