Million on 16 March 2008
The cost of modding your PSP is dependant on the PSP you have , you could "mod" it for free.
You don't "need" a 4GB to download PSP games , You could manage 3 or 4 PSP games on a 1GB ( you'd have to take stuff out Music, Movies etc).
You also don't "Need" a UMD in drive to play an ISO , this varies with games I think.
You could play downloaded PSP games for around $20.
