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Good find, those Compaq mx11800 usually sell for around 30-50 shipped depending on condition. I'd reccomend keeping one or two good quality boards for yourself.
For the Compaq RT101, was there a seperate white stem between the keycaps and rubber dome? These look simular to a dell quietkey, which are fair for rubber dome boards. Not much value in these boards, but a decent layout, and very cool color for the rubber domes.
That black dell, isn't that a Dell AT101W? Black alps are somewhat common, but I'd be very interested in trying some new black alps. Let me know if you ever end up parting with this board.