In the HunterVille mapping competition, one of the “Honourable Mentions” starts without a weapon. Unfortunately I didn´t find the crowbar the author placed near the beginning, so I had to struggle through until I found another one (It was right next to me, so it was completely my fault!)
At the beginning I was incredibly frustrated, but that frustration turned to motivation quite quickly. I knew I must have missed something but I wanted to see if I could still finish the map. FYI, if you throw a desktop computer at a headcrab enough times you can kill it.
The whole episode got me thinking about how I feel when I start a mod with no weapon.
On the one hand, I like it because right from the start I am on the defensive. I can´t go running around without being careful just in case I run into an enemy. I also get a sense of achievement if I find a weapon that has been hidden.
On the other hand, not having a weapon changes the way I view the mod and mostly that is a negative view. I hate not having a weapon, because it goes against the reason for my playing of the mod. I got incredibly frustrated playing Minerva when you lose your weapons for a while.
If I had the choice, I would start with the gravity Gun and a few items I could use to defend myself, that at least would make me more confident in exploring without feeling a need to skulk around.
I would be interested to here the opinions of both players and mappers for this question.