The biggest picoPSU can deliver up to 160W. Usually, any 65W TDP CPU can be powered with the 160W picoPSU-160-XT.
For example, a mini-itx motherboard with an i5-2400s, a SSD and a 2.5" hard drive can be powered by a picoPSU-160-XT.
For higher power CPU's, like i7, you can use the M4-ATX power supply. Note that this psu cannot be installed directly onto the ATX slot of the motherboard.