So the GIGABYTE P35 DS3L is above one hundred dollars now.  Bummer.
 
Which board is the successor to the GIGABYTE P35 DS3L as awesome cheap gamer board?
(also needs to take E8400).

Most likely GA-EP35-DS3L or GA-P45-DS3L
The same applies for GA-P35-DS3R (also unavailable at the moment).
 

Not just GIGABYTE boards.  I mean spiritual successor.  And is also out right now.  

Only x38/48/p45 can allow e8400 to oc to its max of 4.3+ghz. P35 can't do it. They cost twice as much though.

The successor to the P35 is the P45 chipset and will be released in the first two weeks of june. The X38/X48 (same thing) is "above" the P35 in terms of price and capability and is widely available right now.

The p45 should drop below x38/48 as time goes on though. It's meant as a mainstream chipset of a newer generation, to replace p35, while x38/48 is meant as a performance chipset. P45 overclocks almost as well, just don't support Crossfire. Once it drops in price, it should be a good deal.