What are some alternatives?
When comparing Sampulator and BlokDust, you can also consider the following products
Splice Beat Maker - Make and share beats in your browser
Ramsophone - A generative art/music machine. (Be sure to refresh!)
SunVox - SunVox is a small, fast and powerful modular synthesizer with pattern based sequencer (tracker).
Keezy Drummer - Make a beat in seconds
SplitCloud - Play two different songs on each side of your headphones
Mubert - Electronic music generated in real-time just for you