"Can you write a system for money?"

Certainly! Here's a simple money system that includes a leaderboard to display player's money.

1. First, create a server script in ServerScriptService and add the following code to create a leaderboard for players:

```lua
local Players = game:GetService("Players")

local function onPlayerAdded(player)
    -- Create a folder to store player's stats
    local leaderstats = Instance.new("Folder")
    leaderstats.Name = "leaderstats"
    leaderstats.Parent = player

-- Create a money value for the player
    local money = Instance.new("IntValue")
    money.Name = "Money"
    money.Value = 0
    money.Parent = leaderstats
end

Players.PlayerAdded:Connect(onPlayerAdded)

-- Add leaderboard to players who are already in the game
for _, player in ipairs(Players:GetPlayers()) do
    onPlayerAdded(player)
end
```

2. Now, let's create a simple system to award money to players. In this example, we'll create a part that gives players money when they touch it. Create a new part in the Workspace and add a script to it with the following code:

```lua
local part = script.Parent

local function onTouched(hit)
    local player = game.Players:GetPlayerFromCharacter(hit.Parent)
    if player then
        local leaderstats = player:FindFirstChild("leaderstats")
        if leaderstats then
            local money = leaderstats:FindFirstChild("Money")
            if money then
                money.Value = money.Value + 10 -- Change this value to the amount of money you want to give
            end
        end
    end
end

part.Touched:Connect(onTouched)
```

Now, when a player touches the part, they will receive 10 money (you can change this value to your desired amount). Their money will be displayed in the leaderboard created in step 1. You can expand this system to include more ways for players to earn money or spend it on in-game items.