If you don't want to stay with intel, you have the following options :
1) Get an Abit KT7 (Via KT133 chipset)and an AMD T-bird at 1 GHz (that should cost you less than the cusl2 and a piii 800 or even p iii 750) and you can also connect the L2 bridges of the T-bird and overclock it, you can also buy an verclocked guaranteed cpu.
2) Wait around one month untill the VIA KT133A chipset motherboards come out and get one which is overclockable then according to initial reviews you could overclock at higher fsb frequencies, up to 133 fsb if you're lucky. In that case a T-bird 850 should be a better choice if you overclock because you could get it up to 10*100=1000 or maybe 8*133=1064 (if you're lucky or if you buy a guarantted 850 T-bird at 1GHz) or try combinations inbetween. Arguably a 1 GHz cpu should
be more difficult to take up to 133 fsb since T-birds are getting very hot above 1.2 GHz.
3) Wait even longer and get a DDR motherboard, DDR memory and a 133 fsb rated T-bird. The current price of DDr in the few places which sell it is double that of SDRAM at the moment, so its probably better to wait for them to drop.
To find out which is the best solution you can have a look at :
http://www.ocworkbench.com/
they have a test -review of the Epox KT133A new motherboard and comparison with bot KT133 motherboards and the Iwill DDR motherboard, there is also some overclocking information. Also Anatech has a review of the iwill ddr motherboard. If you look around online you can find furhter information.
Of course, if you wait you have also the option of the VIA 266 DDR motherboard which supports intel cpu's. Some of these will also support both DDR and SDRAM memory (although not running at the same time) so you could keep your old memory untill DDR prices go down).
Best of luck with your decision. You got a number of choices there !