66% off is a reasonably good deal as Steam only has 40% off the retail price of £19.99 at the moment.
Summary: Sonic’s universe is thrown into chaos when a mysterious new power comes into force, creating ‘time holes’ which take Sonic and his friends back in time.
Minimum OS Microsoft Windows 7/Vista/XP
Minimum Processor Intel Pentium Dual-Core T4200 (2x2.0GHz) or AMD equivalent
Minimum Memory 2GB RAM (XP)/3GB RAM (Windows 7 / Vista)
Minimum Graphics NVIDIA GeForce 8800 (512MB) / ATI Radeon HD 2900 (512MB)
Minimum Hard Drive 11 GB