I've long recommended 1/4" solid carbide upcut spiral bits in place of standard straight bits. They cut smoothly, last a long time, and you can use them for mortising.
No router bit lasts forever, however. When your bit finally takes it last cut, don't throw it out. Instead, find another use for it.
Here's one example: a card scraper burnisher. The smooth shank of the bit is ideal for shaping the cutting hook on a scraper. I drilled a hole in a piece of scrap and glued the bit upside down with epoxy. Shape the handle into something comfortable.
The exposed shank is ready for use. Since the carbide is far harder than a scraper, this burnisher will last far longer than it did as a router bit.
