Try getting "Advanced Task Killer" (the one with the green robot holding a blue X), it's mainly a good housekeeping app but it also lets you manage multitasking VERY well and lets you switch to and properly close apps straight from the status bar.

There's actually quite a LOT of good streaming radios. My two personal favorites are "XiiaLive Lite [DroidLive]" (it's free--and faaaar better than the N900's streaming player... PLUS it lets me search for stations, even commercial stations... I use it a lot to listen to a few AM talk stations I like to listen to) and the other is "Scanner Radio" (available as free-with-ads or paid-without-ads) to listen to police/fire/EMS scanners (it also lets me search--it even lets me use my GPS to auto-located the scanner channels near me... bet the N900 apps aren't doing that).

I don't much care for the default browser either---I recommend downloading "Dolphin Browser" (Firefox for Android). It's based on the Gecko engine and so renders and works like Firefox... PLUS you can set the agent string so you can fool websites into thinking you're on a desktop PC or even iPhone, in addition to the Android agent string.