iZeby.com is one of the very strong bookmarking websites in our niche due to it's presence on many social bookmarking tolls and widgets. It is highly branded even the site design is very common. Start bidding at $1500!

SharingIt.co.uk is also for sale starting at $800. They claim to have unique design (even it looks a bit outdated) and some Adsense revenue. More details at Flippa.