You could try one of the models from Denpa. The VT-50 Digital Voice Recorder or the MP-38 Digital Voice Recorder. Both products are available with 1Gb memory, the VT-50 records in MP3 format giving 283 hours recording for 1Gb of memory, MP-38 records in WAV allowing 141 hours for the same memory size.

Both have FM radio's and can be used as MP3 players for listening to music during the comute. They can be used with the Digital Voice Recorder Wireless Microphone for remote recording up to a distance of 20 Metres and the Digital Voice Recorder AC adapter. Both Digital Voice Recorders come with an adapter to allow the device to be used for recording telephone calls (non-PBX type).