Most commercially available high-frequency (HF) transceivers are capable of being dialed back to QRP power levels, so chances are pretty good that most hams already have the gear needed to work QRP.

[Pete Juliano, N6QW] built a 20 M QRP CW transmitter using just a handful of parts. That in itself will not raise any eyebrows, until you find that he built it using one of the very first RF ...