I'm glad you asked... I use Canvas 8 (from Deneba Systems) Picked it up once from a magazine cover disk - and it was love at first sight
The application is quite a weird one as it does pixel-pushing (photoshop style, kind of) and handles vector drawing/DTP all from one interface! Basically, it's very innovative and intuitive to use!
For pixel-pushing I still prefer Photoshop - but vector manipulation is just sooo smooth... I love it!
They've done a very good job at Deneba - pity the program is not more popular! It's got few bugs when it comes to exporting - it's not exactly straight forward, but...
For vector drawing I can highly recommend it!
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