I REALLY (ARG!!!!) hate it when the insert/home end etc block of 6 stops being 6x2 and starts going weird or like 2x3! I use those keys all the time when programming.
Far worse than that -- Microsoft's keyboard designers decided to go in for a collective lobotomy some time ago, and redesigned their entire line of keyboards (office, gaming, multimedia, wireless, internet) to use (vertical) island of *5* keys instead of 6.
In their infinite wisdom, they removed the INSERT key, and made the DELETE key double-height instead.
Insert got moved as a tertiary function on the PrintScreen/SysRq key.
I inadvertedly bought an MS wireless office solution (wireless keyboard+mouse). I loved the mouse, but literally returned it to the store within 5 minutes after realizing insert was gone.
The shift-Insert a keyboard combination I use all day long. It's the universal 'paste' command, that works in every single program... Especially if you also switch to Linux or SSH shells regularly, CTRL-V simply isn't an option there.
I now have a 'regular' wired MS optical mouse, and a cheap chinese wireless keyboard that has a normal insert key, a normal 3x2 island, and a normal cursor key layout.
Anyway, those 'special' keyboards were all over the place a year ago. I don't know if MS reverted back to normal ones by now or if they stuck with them, but somoe poking around on the MS website hailed this as a revolutionary change because market research had shown that 'most people never use the insert key, so removing it made their keyboards 'less confusing'. In Microsoft office you could still use the Printscreen/Sysrq/Insert key to switch between insert and overwrite mode, but Shift-Insert was simply no longer an option. *Sigh*.
Don't you love it when a place like Microsoft designs their products for the lowest common denominator?
Now, if only one could get a half-way decent keyboard without the windows keys, things would be perfect.