I personally like these kind of hd's in the portable,  they were pretty common in the PM 6100's

( notice the power requirements )  in the picture.. compared to the stock conner drive…  yup much lower

http://www.ebay.com/itm/Quantum-Trailblazer-TRBLS-50-pin-SCSI-700-MB-3-5-HDD-TESTED-Free-Shipping-/200933868581?pt=US_Internal_Hard_Disk_Drives&hash=item2ec8978425

other wise just get your self a 2.5 to 3.5 scsi adaptor … they use to be on ebay, i didn't see any just now.

no need to worry about termination it will just work using a powerbook hd…  but scsi powerbook hd's are crap and

just when you get use to it working… it won't work.

and there is always aztechmonster… looks like he has lowered his price due to the popularity of the SCSI2SD

and of corse there is SCSI to sd.

but my over all favorite drive in the portable is the those 500-700mb quantum drives .. they are quiet and very energy efficent.

Here is another one… Quantum Trailblazer is the name of the scsi 50 pin drive.

http://www.ebay.com/itm/QUANTUM-TR700S-655-0244-700MB-SCSI-50PIN-Drive-Tested-Warranty-Ship-Intl-/311038006953?pt=LH_DefaultDomain_0&hash=item486b4f56a9