My "Queen of the Night" orchid cactus blooming in late May 2013. (In fact, all of the blooms on this page are from around the same time, all taken within about a week of each other.) This bloom, which is open for only one night and then wilts the next day, is about 7-8 inches across.
Another one of my orchid cacti. I'm not sure what this one is called, but I love the bright pink color. This bloom was about 6 inches across.
This one is called simply a "red orchid cactus." Unlike most other orchid cacti, which don't do well in direct sunlight, this breed does quite well with small amounts of direct sun (though no more than about 2-3 hours per day). Its bright red blossoms tend to be smaller, averaging about 4 inches across.
Here's another shot of my Queen of the Night cactus, this time with the bloom not yet all the way open.
Here are two other types of jungle cacti, but not of the orchid cactus variety. The one on the left is a "rat-tail cactus," while the one on the right is a close relative known only by its scientific name, Aporophyllum.
This is known as a "Memorial Day" cactus (because it tends to bloom in late May), and it does best in partial sunlight—basically in a screened area where the sun is filtered somewhat. It's a fairly close relative of the better-known Easter and Christmas cacti.

All of the plants above are different types of jungle cacti. But most of my plants are good ol' desert cacti. They just tend to bloom later in the year. But this one is an exception. It's a Mammalaria, which blooms for me nearly every spring.

When I get more blooms from my other cacti and succulents (I have over a hundred of them—although usually only one or two dozen bloom in any given year), I'll post them here.