I use [link|http://www.polarbar.org/|PolarBar] mailer for e-mail, and it works well, especially with the IBM VM. It's not as slick as PMMail, but works well for me.
I'm currently using [link|http://www.appgen.com|MoneyDance] for finances; it's plenty fast on an Athlon and does everything I need. It's $40.
Another Java program that I've tried a bit (although again, it's not as slick as a native program would be) is [link|http://www.bigzip.com/|BigZip] but it's worked fine for me so far.
ObjectDesktop has an integrated archiver, but I doubt it's available.
[link|http://www.freshmeat.net|Freshmeat] is a valuable resource, even if you're not running Linux.
I'm know I've got some IBM JDK's on my hard drive, plus an IBM registration or two, so if possible I'll include these on CD-ROM with Warp.
Tony