I felt like posting this here for the lulz. It's interesting to spoof a -1ms and 0ms ping on the actual client without using a proxy at all.

You'll need to get WPE pro if you want to do this.

WPE filter for 0ms and -1ms ping: http://dl.dropbox.com/u/13099063/0ms%20and%20-1ms%20ping%20filters.flt

There are a couple filters here. If you want 0ms ping, tick both filters. For a -1 ping, simply choose the second filter.

The reason for both is because the first part of spoofing 0ms requires me to set the length WORD of packet 0x50 from 0x3A to 0x32. I then replace the last 9 bytes with a null, followed by a SID_PING packet whose DWORD value is 0. This is supposed to prevent Battle.Net from sending another SID_PING packet, right? It actually does send me that packet... That's where the -1 filter comes in. Instead of blocking the client from replying (this actually prevents logging in), I tell the client to replace the reply with two SID_NULL packets.