Windows – Weather Logging Software on Windows Home Server

On the RAID requirement, Windows Home Server (WHS) uses its own Drive Extender (DE) technology instead of RAID. This treats installed drives as one large 'storage pool' rather than as separate hard drives and as long as you have two or more physical hard drives installed it will duplicate data across the drives to safeguard it against disk problems.

This is already giving you RAID's redundancy/backup and drive pooling capabilities natively as part of the OS, so depending what you want it for, you may not actually need a hardware RAID controller at all. In fact, depending on what RAID configuration you go for and how much you understand about how RAID really works, it might actually be a very bad idea to use RAID on a WHS.

One of Microsoft's coders has a good comparison of RAID vs DE here Windows Home Server's Drive Extender vs RAID, and the official WHS Team Blog explains exactly why they didn't use RAID here Why RAID is not a consumer technology.

Essentially RAID is best used in two different scenarios, either you want a blazingly fast hard disk system, but don't really care if the disks die and you lose the data; or you're using RAID in a proper server where there's a dedicated team of people who'll be running full regular backups of the data very regularly and will have monitoring tools to alert them when any of the drives start dying and need replacing. It's going to be quite rare that either of these are true for a home server where you're probably storing valuable data and won't be running 24 hour monitoring and alerts with hardware suppliers sending you replacements under SLAs measured in hours.

Something like a Synology DS410 might work or the higher end DS1010+. It doesn't support Squeezbox but does have a streaming service (among many many other features). ~Edit, it actually does support Squeezbox

One of the Synology devices seems to be the most efficient solutions offering quite a few features for a decent price, and I believe it meets most of your requirements.

There is also comparable boxes from QNAP, such as a TS-419P+, either system costs around $600. Otherwise a custom built server, like the one madmaze mentioned, using a linux distro is probably the cheapest, most flexible (although hardest to setup) option.