Watching #LGR's bubblejet video makes me sad I can't get cartridges for my DesignJet 488CA anymore. Oh the fun I had unclogging cartridges with my vacuum cleaner and the simple adapter I made!
Just a block of wood with a hole the size of the vacuum hose and a piece of foam with a slot for the inkjet cartridge. Worked amazingly well to unclog a cartridge.