I'm gonna pop a cap in your… nah I can never pull off gangsta.
Depending on your attitude you either think the TrackPoint mouses between the keys on ThinkPads are either fantastic or dreadful. I love them, I've always been far more accurate with them than with trackpads or those trackballs older notebooks had. With all the multitouch gestures Apple now bundles with their laptop trackpads it's doubtful I'll ever get to use a TrackPoint mouse on a Mac, but I'm enjoying the experience again on my second hand ThinkPad X40.
Not only that, but as a *nix user I also love having three dedicated buttons which lets me copy and paste text in terminals as well as having the usual right click menus. Look at the mouse go! Click! Whoosh! Zoom! Blaz! Blaz?
Anyway because I got this machine second hand I quickly wanted to replace the gungy TrackPoint cap. You can buy a set of replacement TrackPoint caps from Lenovo but they're a whopping $25 so I went on eBay and picked up a set for a couple of bucks from a friendly guy in Melbourne.
The little bag of caps (product ID 73P2698) come with three different styles you can choose: the classic dome, soft dome and a concave soft rim. All three are great but I prefer the concave soft rim (top right in the photo I took above) because it fits the shape of my finger and I can apply much more pivoting force with less effort. By pushing on the edges I can also accurately move the cursor just one pixel in any direction with no effort at all. It's a beautiful thing.
If someone made an aftermarket TrackPoint mouse for Apple notebooks I would buy one in a heartbeat! I'd forgotten how much I love them.