Price: £10 per month
Spotify costs £9.99 per month for new users, and allows an unlimited amount of ad-free streaming via its excellent desktop application.
Spotify for Windows is stable and fast, and we've never noticed a delay shuffling between tracks on a fast broadband connection. But it's Spotify's mobile option, which allows you to stream over a 3G connection, that really appeals.
In our tests on a Nokia E71, we experienced a few difficulties – Spotify requires a strong 3G connection to stream music reliably. But if you find yourself struggling, you can download up to 3,333 tracks to listen to offline. Not only does this remove the problem of weak 3G connections, it means that you can listen to virtually any track you can think of even if you're underground.
The only problem is that once your subscription expires, your portable music does too – although you can still play it from the application, just as before. But the lack of any real ownership of your music is a shame.
Price: From £6.50 per month
Sky Songs offers the secondcheapest basic subscription here at just £6.49 per month. In return you get unlimited use of Sky's browser-based streaming service and 10 music downloads per month.
Alternatively, for £7.99 per month, you can have the same all-you-can-listen-to streaming service and up to 15 tracks to download and keep. It's excellent value for money, and we had no trouble finding the very latest tracks to listen to.
The use of a browser for streaming is a slight annoyance – if a tab crashes and brings down your entire browser, the music stops. Still, the browser-based player is fast, with a negligible delay between choosing a track and playback beginning.
It supports the creation of playlists, which you can save and play from anywhere. You don't get a connected mobile option in return for your subscription, unfortunately, so the only way to take advantage of Sky when you're out and about is to download tracks ahead of time.
Still, in terms of cost-per-download, Sky leads the way.
Price: From £5 per month
Napster is the grandfather of the online music industry – it was largely responsible for the explosion of illegal file sharing back in the 1990s. Now firmly into its teens, it's growing up and sports a respectable face.
In terms of absolute price it's the cheapest here – you can subscribe for just a fiver per month. In return you get to stream music either through a web browser or via Napster's excellent stand-alone application.
There's even a mobile option, although this only allows you to stream 30 seconds of a song or purchase a track rather than being able to listen all the way through, as with Spotify. Your £5 also gives you five unrestricted MP3 downloads per month – a fair deal for those who'd rather stream music than keep it.
If you'd rather download and keep your music, then Sky Songs offers slightly better value for money per track. But for simply listening to anything from a library of 10 million tracks, Napster is superb value.
Price: From £6
eMusic is the odd one out this month. It's a subscription service, but you don't actually get to stream music, which feels restrictive after being able to listen to anything in the libraries of Spotify, Napster and Sky Songs.
Instead, eMusic's subscriptions – which start at £5.99 per month – give you 12 tracks per month to download. The packages go all the way up to £24.99, which allows music addicts 75 downloads every 30 days.
The good news is that eMusic is terrific value: even its most expensive option is considerably cheaper than iTunes at just 50p per track. It's also simple – you buy tracks through eMusic's tiny application, and there's no new player to learn because tracks simply play through whatever you already use.
The drawback is label support. If you're a fan of pop music, you should look elsewhere. eMusic doesn't have deals with the major labels, which means that many chart hits are conspicuous by their absence.
For finding new acts and indie music, though, eMusic represents superb value for money.