The Nook Color got an Android Honeycomb SDK port a while back and Divine_Madcat @ XDA keeps on improving it and recently released the Release Candidate 1 of his Honeycomb Hybrid SDK port for the Nook Color. Using the work started by deeper-blue and a system dump from the Asus Eee Pad Transformer the port is starting to become usable with many things working and of course others not working yet.
The following YouTube video shows you Honeycomb running on the Nook Color, this is the Honeycomb Hybrid RC1 release:

In case you want to install Honeycomb on your Barnes and Noble Nook Color, you can download the Honeycomb Hybrid RC1 release @ http://forum.xda-developers.com/showthread.php?t=1062626.
You will need to root / jailbreak your Nook Color first, see our instructions @ How To Root Your Nook Color.
You can see the changelog below [from XDA]:
RC3 - 5/6/11
- Fixed Calendar
- Updated build.prop
- DPI set to 140
- Installer no longer wipes out data; all future revisions will leave user partitions alone
- Cleaned up some unneeded programs
RC2 - 5/5/11
- Fixed SU
- Fixed Sound
- Fixed Market
RC1 – Release
For more information go to the XDA thread @ http://forum.xda-developers.com/showthread.php?t=1062626.
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