Back in October, the great crew over at Lifehacker put together a list of ten things you can do to boost your Wi-Fi connection's performance. Having glossed over the list and performed a few tweaks myself, I definitely recommend giving their advice a go. Not only was my connection's range improved, but my latency decreased noticeably as well.
If you're heavy into hardcore PvE or PvP content and are strictly limited to wireless connectivity, these recommendations could prove very useful, minimizing your lag and therefore improving your performance. Heck, even if you simply want to enjoy some casual gaming or browsing from your couch, these tweaks would definitely make the experience much easier to enjoy.
Very worth it in any case, if you ask me. =)