I got into an argument about romanization today. Here's "the only romanization system that doesn't suck, even though it's not a standard".

僕はboku wa
aiueo遠いtooi
クヮキェ問うtou
kakikukekogagigugegokwakye (etc)問おうtoou
せぃぜぃ鳳凰houou
sashisusesozajizuzezosizi
てぃてぅかったkatta
tachitsutetodaji/dji*zu/dzu*dedotitu
つぁ
naninunenotsa
ふぁふゃ未来へmirai-e
hahifuhehobabibubebofa (etc)fya (etc)
ほぅ
mamimumemopapipupepohu
yayuyo
ウィヴァ
wawo/-owi (etc)va (etc)君をkimi wo / kimi-o
幻影gen'ei or gen-ei
n

* as pronounced in context

きゃきゅきょぎゃぎゅぎょ
kyakyukyogyagyugyo
しゃしゅしょじゃじゅじょ
shashushojajujo
ちゃちゅちょぢゃぢゅぢょ
chachuchoja/dja*ju/dju*jo/djo*
にゃにゅにょ
nyanyunyo
ひゃひゅひょびゃびゅびょ
hyahyuhyobyabyubyo
みゃみゅみょぴゃぴゅぴょ
myamyumyopyapyupyo
りゃりゅりょ
ryaryuryo

* as pronounced in context

All else as predicted from the above, or in the case of katakana extensions, the obvious phonetic meaning for which the sequence exists in the first place.