You can join all categories using NXT:

"<0.1 BTC" – NXT: 8855983961838503052 http://87.230.14.1/nxt/nxt.cgi?action=3000&acc=8855983961838503052
To join this category you have to send a NXT amount worth below 0.1 BTC to the address and message me the transaction ID and the hash of your password. (How? See the FAQ below)

"0.1<>1 BTC" – NXT: 8855983961838503052 http://87.230.14.1/nxt/nxt.cgi?action=3000&acc=8855983961838503052
To join this category you have to send a NXT amount worth between 0.1 BTC and 1 BTC to the address and message me the transaction ID and the hash of your password. (How? See the FAQ below)

">1 BTC" – NXT: 8855983961838503052 http://87.230.14.1/nxt/nxt.cgi?action=3000&acc=8855983961838503052
To join this category you have to send a NXT amount worth more than 1 BTC to the address and message me the transaction ID and the hash of your password. (How? See the FAQ below)