Three plug-ins that are part of REAPER have been released as stand-alone VST plug-ins (preview versions).
ReaGate is a very configurable gate with wet/dry controls, lookahead (on hosts that support PDC), hysteresis, hold, noise generator, MIDI event sending (on hosts that support it), built-in filtering sidechain as well as supporting sidechain inputs, and more.
ReaComp is a compressor that has a lot of controls (wet/dry/pre-comp/sidechain/knee). It also has a program dependent auto-release mode.
ReaFir is a FFT-based EQ/dynamics processor/noise removal/analysis plug-in. ReaFir can do a lot of types of processing, from standard linear FIR-based EQ, to noise signature detection and removal to per-band compression and gating.
So note, this is a preview release which has been tested on a number of hosts but might not work for your particular setup.