New from Canopus, the ADVC300.
I'm afraid it's rather expensive, but it looks impressive.

Clean, stabilize and preserve analog video
ADVC300 employs advanced 3D YC separation, 3D noise reduction and Line Time Base Correction (LTBC) functions for perfect frame synchronization. Poor analog source video is filtered and stabilized prior to DV conversion. ADVC300 is also ideal for “cleaning” old analog video and output back to analog tape.