From the publisher:
Think you have enough crunch to choose from? Think again! The 101 Series Subscription gives you – yes, you guessed it – a succession of books to help you realize your vision of your character. Products like best selling Feats 101, 101 Magical Weapon Properties, 101 1st Level Spells, and 101 2nd Level Spells.
The 101 series brings you pure crunch: feats, spells, and magic items. For the first year, we will bring you the most popular game mechanics based on subscriber input (right now that is spell levels 1-6). Then we will open up it further based on subscriber input. We plan to create traps, hazards, optional class abilities, optional monster abilities, or whatever our subscribers demand.