$processes = Get-Process | Select-Object @{Name='Name'; Expression={$_.ProcessName}}, `

@{Name='PID'; Expression={$_.Id}}, `

@{Name='Session#'; Expression={($_ | Get-Process | Select-Object -ExpandProperty SessionId)}}, `

@{Name='Mem Usage'; Expression={"{0:N0} K" -f ($_.WS / 1KB)}}

Format the output similar to tasklist

$processes | Format-Table -Property @{Label="PID"; Expression={"$($_.PID)"}; Width=10},

@{Label="Name"; Expression={"$($_.Name)"}; Width=25},

@{Label="Session#"; Expression={"$($_.'Session#')"}; Width=10},

@{Label="Mem Usage"; Expression={"$($_.'Mem Usage')"}; Width=15}