First, there is an alternative to eMule called iMule which apparently is similar to aMule and uses I2P for safety but apparently only supports the KAD part, not ED2K.
Or you can use eMule over a VPN connection. There are lots of providers of this for around €5/month, but the one I first tried doesn't support port forwarding and thus I was lowID in ED2K and Firewalled (with "Buddy") in KAD. Most VPN networks are like that.
I've found only one exception: this VPN provider which allows you to set up port forwarding. Costs €10/month unfortunately, or €0,5/GB. Speed was high (hundreds of kB/s).
An alternative to VPN is the Tor network, but I doubt it supports port forwarding.
I also saw this thread on using "VPnetMon" to make sure it doesn't switch to the ordinary connection if the VPN is down. It seems like a good idea to have (I've read several times how VPN connections may fail occasionally, and then Windows is smart enough to automatically switch to the unsafe ordinary internet connection..) VPNetMon works very well. Be sure to install Microsoft .NET 2.0 first. And I set "soft shutd time" to 10 secs for eMule (at first it was 500ms, then eMule shut down so fast it corrupted the known.met file).
And regarding discussion if PPTP is safe, I've concluded that it is (provided it uses MS-CHAP v2), when it comes to being invisible from authorities while sharing files (the weak part, as I understand it, is if you use a too simple password and a hacker attacks). Many VPN providers also have IPsec which is apparently safer than PPTP.
An alternative (or complement) to VPNetMon could be to set up your firewall to just allow connections to local IP in the range 1.2.0.0 to 1.15.255.255, but not all firewalls can manage that, and it can be cumbersome to handle IPv6.
Mu conclusion is that for me, eMule + Ivacy + VPNetMon is the best solution, with PPTP or IPsec.
This post has been edited by DavidGGG: 10 May 2009 - 09:16 AM