OÓ.com is not in any language, it is a really quite easy to remember domain, and its punycode is "xn--o-vga.com".
NÉG.com it's related to negotiations. It is an abbreviation known all over the world, what does the domain too intuitive. The punycode is "xn--ng-bja.com".
ÍDEM.com: The word "ídem" means "the same" in Spanish. And in English has the same meaning, but it is written "idem". The punycode is "xn--dem-qma.com".
Físico.com: The word "Físico" is a Spanish word and it can refer to "Physical", "Physicist", or "Physique" in English words. This domain has a lot of uses. The punycode is "xn--fsico-zsa.com".