This is a simple Chrome extension which allows the user to switch between multiple bookmark bars. I use the bookmark bar a lot and it got rather full. I got around this by making folders for each type of bookmark I had. Then it struck me that I would rather have a specific set of bookmarks available for each task.
GPL v3 Repository
Currently it only handles creation of new bookmark bars. Removing and renaming bookmark bars can be done by editing the bookmarks stored in the "BookmarkBars" folder. Be careful when renaming manually as this can cause problems. Removing a bookmark bar folder, re-ordering them or editing the bookmarks within should be fine.
Caution should be observed when using this in conjunction with a bookmark synchronizer. Firstly you must synchronize your bookmarks after installing it on your first machine and before installing on additional machines. If the bookmarks aren't up to date you can end up with multiple "BookmarkBars" folders which can be confusing. If you see multiple "BookmarkBars" feel free to delete the additional ones, just make sure you keep the one you are actually using. Secondly, make sure to always have the Default bookmark bar selected when synchronizing. Failing to do so can end up combining the two (or more) selected bookmark bars. If you can't control when the bookmark synchronization happens you should probably avoid using this extension.
The extension is in early beta testing and is provided as is, I suggest you back up your bookmarks before using it. It is open source and available under the GPL v3 license.