Standard interviews: multiple choice trivia, red black tree programming puzzles.

Innovative interviews: Custom code exercises with custom unit tests written by the company, ssh exercises where a server is created automatically per candidate and he has to connect to it and configure/fix/change some stuff.

After many interviews (both given and received). I have definitely settled that:

1) I'd rather write a stupid program on HackerRank than deal with an annoyingly scheduled phone interview (where I might be expected to spell that code over the phone WTF). Automation is nicer than the average interviewer. A proper code editor for coding is better than the average shared editor.

2) No matter what we try to do: 20% of candidates won't show up + 20% won't be able to code a program to print numbers from 1 to 10. There's nothing we can do about that (the sad state of interviews is probably all because of that).

3) For the first initial screening, very simple exercises are all that's needed (see 2). Hacker Rank is perfectly appropriate for that.