Is that possible? I plan to only boot into one distro at a time but what if one is Rieser and the other Ext3? I am going to resize the Suse partition with the Mepis live disk to make room for a Mepis hdd install.

No problem at all...
from this page here,
link:

http://www.faqs.org/docs/linux_admin/x1762.html

I see that:
(quote):

"A swap partition is also not special in any way. You create it just like any other partition; the only difference is that it is used as a raw partition, that is, it will not contain any filesystem at all."

(/quote)

So, there is no filesystem on the swap partition.
And, in my experience, the swap file is automagically detected and used by every distro that is installed to the system.

I am confident someone will correct me if I'm wrong.

Yes, correct. I have 5 distros sharing the same swap partition. Most distros have a custom or expert install option for partitioning. Pick that and set root to the partition that you made for Mepis and also tell it to use the existing sweap partition.

Be aware, that you need to use lilo or grub as a bootloader. So, if the option is there, tell the second distro to install lilo or grub on a floppy. You can then add the Mepis install to Suse's bootloader when you are satisfied that all looks good. That is if you want to keep the suse bootloader.

Alternately, if you elect to use the Mepis bootloader, then it may automatically add Suse as a boot option. If not, then you can add it manually.

Thank you for your answers. I suspected a single swap partition was multi distro usable. Thanks for you confirmation. About grub, they all do the same job with different graphics so if the Suse grub gets overwritten with a new grub that will automatically add all existing os's, that will just save me the hassle of manually adding. Thanks for that extra information though.