What File Format??!!!!!!!

I ma reletivly new to direct 3d programing but i am good at dd with c++. anyway: what is the best and more flexible file format in the indestry, i cheked out the X file format but did seem to flexible... i have made a ckrappy md3 file loder, perrty good. i am just trying to find out a good file format that is suported by some inexpensive 3d modling software and shuld be ''not-to-hard-to'' export into the d3dx8 api. are thare and 3ds exporters out for download, maby some engines that heavaly suport one file format and vave an awsome exporter that does the job... ? AfTeRmAtH