NGC 2024, the Flame Nebula, is beautiful but is usually overshadowed (literally) by the bright star Alnitak just off image to the top.
NGC 2327, the Seagull Nebula, contains many star clusters and emission nebulae in its span of 100 LYs.
NGC 6334, the Cat's Paw Nebula, 5500 light years away in Scorpius
NGC 1499, the California Nebula, is a 100 light year long emission nebula located 1500 LY away in the Perseus
OU4, a recently discovered oxygen nebula with SH2-129 in the backgound
NGC 2264, containing the Christmas Tree cluster and the Cone Nebula both towards the bottom
IC405, the beautifully textured Flaming Star Nebula located 1500 LY away in Auriga
M20 is named the Trifid Nebula for the way the red emission region is divided into sections by dust lanes
Sh2-155 is named the Cave Nebula for the bright feature in the lower left corner.
Simeis 57, the Propeller Nebula, is point symmetric but it is not clear how it was formed
Sh2-254 is rarely imaged despite having a unique structure
Sh2-302 is lovingly referred to as the Snowman Nebula and is one of my favorite obscure objects
This feature is nicknamed the Dark Tower of Scorpius, sounding more sinister than it appears to be
Sh2-170, a beautiful unnamed object in Cassiopeia
Sh2-15 is a beautiful yet obscure object - this is the first image of this object on the worldwide database
Sh2-276 is part of the wide Barnard's Loop which forms a half circle around the Orion constellation
Cederblad 51 is a rarely imaged area which I find fascinating for its complexity