I really like Wunderlist. In the past few months, they seem to have fixed their syncing issues, so mobile and desktop are pretty seamless now. I keep tons of ideas in Wunderlist, and the search works pretty well if I just brain-dump some keywords into the todo item.

I also made a thing to suck all the Github repos you star into Wunderlist with their descriptions, since I always want to find something I starred in the past, and I've found Github's search lacking in this regard: https://github.com/ip2k/wunder-star