What was your worst touchpad experience?

We all know Windows laptops are not the greatest when it comes to touchpads. I know it probably varies by OEM and price level, but for the most part they are rather bland and pedestrian. My worst experience has to be on my other laptop I own. The touchpad on my Dell Vostro 3550. It has just an awful touchpad, it randomly locks up, it moved the mouse all over for no reason sometimes. It is just horrid, I always use a mouse with it. The touchpad on my 2011 HP Pavilion dv6z is slightly better it at least gesture support, pinch to zoom etc. although it doesn't work very well.