These are my digital audio recorders used to document investigations, and EVP (electronic voice phenomenon). From left to right:
RCA RP5007: This recorder uses smart media memory cards, so I can record as long as I still have memory cards left. It isn't working right now however.
Olympus VN-1800: My favorite of the all the recorders, records about 1 hr 15 min in SP mode, but the quality is GREAT. When used with an external microphone the microphone sensitivity is amazing.
Diasonic DDR-1232: An older recorder that will record for 12 hours in SP mode, which would be great, but the quality isn't that great. It is mainly used as a backup recorder, in case I need more record time, I have 12 hours waiting for me!