of the other commonly installed ones, there are samba, openwrt,
strongswan and ipsec, that I know of. All these are packages that
haven't been installed or tested for a while (by me, anyway)...

I have strongswan running on my 3800 with v3.10.24-8.  I've found some interesting results comparing it against another platform I have.  I may (or may not) have found some bufferbloat-ish behavior in IPSec (where it forms a bottleneck doing the encryption/decryption).  More on that when I get clearer results.

-Aaron