Seriously.. what I wouldn't have done to have had a chance to get this shot at the proper angle.. I just couldn't get around that darn thingie to get the shot from the side...
I just wanted to share it with you... as far as I can see, it's a wasp eating a hoverfly more or less...
Cool that you posted this. Fishermen/women always talk about the one that got away but I think the fact that you can actually prove it w/ macro shots oof is even more tantalizing and difficult to swallow. Oh well, learned something for next time maybe.
I feel your pain! Consider this the first of 1000's of missed opportunities. It happens all the time. It makes the ones that you do get even more satisfying. You'll get plenty of reasons for missing the shot;
1) bad angle....something in the way.
2) bumped the leaf, bush, etc with my lens / flash / hand
3) Forgot to turn on the flash
4) flash batteries dead
5) camera batteries dead
5) No CF....yes it happens
6) have the camera set to the wrong mode
I always try to double check 3 - 6 before heading out, but sometimes an opportunity comes up and you don't have time.
Don't you hate when that happens! Oh well there is always something going on. I found the more you do this, the easier it is to find the bugs. There will be other opportunities.
I saw people post pictures of Jumping Spiders with prey and I never saw this. A month ago I found 3 different Jumpers with prey within an hour. You never know what you are going to find.
The cool thing is every time I have gone shooting macros, I always see a new type of bug. I mean every time.
90% of my macro shots end up like this, especially when handholding the camera; keeping things steady and in focus isn't for the faint of heart. Nice try!
I feel your pain. A month ago my wife and I were hiking in the woods nearby, and a mother and baby Armadillo came by. Just a few cm away! No fear at all! Wouldn't stop moving at all, and worst of all, were INSIDE my minimum focus (about 1 meter) on the lens! I guess that is number 8) too close to focus.
Cool stories. I particularly like the one about the bugs being inadvertently flung into the next field. It hasn't happened to me but I am now tempted to try it.
But yeah... Macrophotography is still new to me.. and I'm sure I will have more experiences like this... I just remember when I saw it and managed to take this shot of it.. I was thinking, "Damnit.. can't get around it... ".. and then it lifted off and flew away out of reach...
Oh well there is always something going on. I found the more you do this, the easier it is to find the bugs. There will be other opportunities. 
You never know what you are going to find.
Tim...