Most of my cakes are labors of love because they're done for friends/family/co-workers. I do usually get reimbursed for my cost, thankfully!
My best (worst?) labor of love was my very first cake- that I did for my wedding reception! I had no budget for cake, so it was either make my own or get one from Walmart (no!). I did several practice runs, and I figured I could do it. It was 3 tiers, wrapped in ribbon, with little vines and tiny flowers scattered around it. The decoating came out really well! However- we got married in July and I made the mistake of putting the cake in the fridge for a little while before transporting it in hot cars. Yeah. It was a bit melty when we got there, and the fondant was somewhat bubbly. It still looked ok, and people were impressed that I'd made it myself. But damn, it took me FOREVER. It tasted good, though! I wish I had a pic but only have a hard copy. One day I'll get around to scanning it in.