Get the Oatmeal right here.
VST Synth with waveform-editor
The fabulous and free subtractive synth Oatmeal by Fuzzpilz features 2 oscillators plus 1 noise source, 5 envelopes, 2 LFO's, XY-pad, an arpeggiator, and portamento/ glide. Oatmeal comes with several onboard effects: delay, chorus, reverb, eq, and distortion. But the best part of this vst synth is it's waveform-editor, that lets you design and use your own waveforms and LFO's. A lot of fun and highly addictive!