There are many other CryptoNote coins but their communities, usage, trading volumes and hashrate are much smaller than Monero. Here is a chronicalogical graphic of many of the coins and from where they were forked:
You mentioned Boolberry, which like Aeon was an innovator in the area of pruning. Boolberry was popular early because (in addition to pruning) it was the first CryptoNote coin with a working (but very basic) GUI. Its developer has been inactive for some time. Aeon has a visible lead developer (smooth) that is also a Monero core developer, so Aeon has received far more attention than Boolberry recently.
Many CryptoNote coins appear to have been created by the same parties:
Measured by Bitcointalk activity, I would estimate the most active CryptoNote communities are currently:
- Monero (XMR) largest community (RingCT, LMDB, OpenAlias, tail emission, etc)
- Aeon (AEON) (pruning, focus on low memory footprint)
- Boolberry (BBR) (pruning)
- DigitalNote (XDN) (PoA development following multiple name changes)
- Bitcedi (BXC) (XDN fork with slower emission)
- Bytecoin (BCN) (First CryptoNote, compelling evidence of fake creation date)
- Dashcoin (DSH) (automated BCN fork without huge "premine")
- Pebblecoin (XPB) (PoS)
All have operational blockchains and varying level of developer activity or complete absence of activity.