Forum OpenACS Q&A: Re: Is a shared and managed hosting option avaialble ....

I'd second acorn hosting (www.acornhosting.com - I use one of their virtual server services).

The limitation is that the service I use is really for low/medium volume sites, but it would be worth asking about your specific requirements. Cathy Sarisky is very responsive.

For me here's not much admin involved, except vacuuming the db (and if you use a 7.4 Postgresql, the pg_autovacuum in contrib fixes that) and backing up (for which a number of automated solutions are well documented).