The MindWave from Neurosky is a one active channel device. It has been available for a while. It retails for about $100 and comes with ten apps and many more are available (see http://www.neurosky.com/Products/MindWave.aspx). I have tried it and it seems to work, and it is great that it can be used with third-party software such as BioExplorer and BioEra. However, I find it very uncomfortable. It might be fine for a child but not for someone with a big head like mine!
There is an earlier version (MindSet), which was the first mass market neuroshaping device
introduced in 2009. It has earphones and looks more comfortable. It uses the same chip set as the MindWave. NeuroSky provides a comparison chart that shows the capabilities of each of their products (see http://support.neurosky.com/kb/technology/what-are-the-differences-between-the-mindset-mindwave-mindwave-mobile-and-mindband).
Another company promises to introduce the Melon, originally called the Axio. It is based on the NeuroSky chip. It is an attractive and comfortable appearing three sensor band, which is adjustable to different head sizes. Again, they exceeded their goal in crowd-
The Muse was developed with Interaxon's own chip set and technologies. The device has seven sensors and four active channels (AFp3, AFp4, TP9, TP10), which are on the forehead and around the ears. Detailed technical specifications are now available (http://s3.amazonaws.com/totem_production/assets/other/5987/Muse_-_Tech_Spec_Sheet_CES_-_2014.pdf?1387319049), and they look quite respectable.
The producers of the Emotiv EPOC 14 channel device are developing the INSIGHT, which is a five channel device. Again, they exceeded their kickstarter goal of $100,000 by over $1.5 million (https://www.kickstarter.com/projects/tanttle/emotiv-insight-optimize-your-brain-fitness-and-per).
The INSIGHT was originally promised for the summer of 2014, but the release date is now December 2014.
The ENOBIO from Neuroelectrics (http://www.neuroelectrics.com/enobio) is a very promising, but expensive high end device. It comes in 8 channel, 20 channel and 32 channel configurations. It uses dry electrodes and bluetooth. This one is definitely on my wish list, and it is actually available now.
Please feel free to comment or, if you wish, direct questions and comments to me directly at drampsych at gmail.com.