Canon has today released version 3.6.1 of their TWAIN drivers, these are compatible with the S10, S20, S100, S300, EOS-D30, G1, Pro 90 IS, A10 and A20. These updated drivers have improved speed for RAW file conversion as well as a new standalone utility (RawConverter) for converting from .CRW (Canon RAW) to TIFF. Drivers are available for Windows 95/98/98 SE/Me/2000 and Mac OS 8.1+.

Click here to download Canon PowerShot drivers

UPDATE 10/Apr/2001: Ok, I've NO IDEA what's going on but it looks as though Canon have pulled the 3.6.1 drivers, the above page has reverted back to the 3.5.0 drivers... No, I've no idea why.

Thanks to forums poster Nadim for spotting this before me!