One of my favourite games in the last decade, Natural Selection, does this really well. When you die, you are put in a respawn queue, and you respawn from infantry portals. The more infantry portals your team has built, the faster the queue is drained, but also the more resources you've spent doing so. There's also a rather expensive option the team commander can trigger that will bring all dead players back to life all at once.

It's a nice way to get people playing instead of sitting around watching, but at the same time placing a cost on dying that simply doesn't exist in most multiplayer shooters today.