Lesson learned:
1.) Low End Mac is the place to find out about old, um, low end Macs. 1400 info here: http://lowendmac.com/pb2/1400.shtml

2.) There is no cheap G3 laptop out there, no matter how creative you are. You'll either be much too feature poor (1400 + G3, or a clamshell iBook without the power to really run OS X -- and you'll try) and/or you'll have spent so much you'd've been better off buying a new iBook for $1000.

3.) Fortunately, a 603e in OS 8.1 or 8.6 is plenty.

4.) Maybe the best news of all is that you can still use Airport with the old beasts!! (http://www.penmachine.com/techie/airport1400.html)

Still waiting for my eBayed Orinoco card to come in. My 1400's 48 megs of RAM almost runs CodeWarrior 5 for Java and OS 8.1, and runs MacWrite, no problem. Very easily upgraded hard drive -- as many gigs as you can stand if you partition. You can't say that about an iBook.

Oh, and...

5.) If you want Linux, run like the wind *away* from the 1400. When you start looking for how to support ethernet on the 1400 with MkLinux and stumble over how easily gentoo can be used on other 603e 'books, well, you know you got the wrong box for Linux. Course if you only want Linux, there *are* other, blasphemous, inexpensive, highly-compatible x86 laptops out there...