Can I get detailed exception stacktrace in PowerShell?

There is the automatic variable $StackTrace but it seems to be a little more specific to internal PS details than actually caring about your script, so that won't be of much help.

There is also Get-PSCallStack but that's gone as soon as you hit the exception, unfortunately. You could, however, put a Get-PSCallStack before every throw in your script. That way you get a stack trace immediately before hitting an exception.

I think one could script such functionality by using the debugging and tracing features of Powershell but I doubt it'd be easy.

There is a function up on the PowerShell Team blog called Resolve-Error which will get you all kinds of details

Note that $error is an array of all the errors you have encountered in your PSSession. This function will give you details on the last error you encountered.

function Resolve-Error ($ErrorRecord=$Error[0])
{
   $ErrorRecord | Format-List * -Force
   $ErrorRecord.InvocationInfo |Format-List *
   $Exception = $ErrorRecord.Exception
   for ($i = 0; $Exception; $i++, ($Exception = $Exception.InnerException))
   {   "$i" * 80
       $Exception |Format-List * -Force
   }
}

Powershell 3.0 adds a ScriptStackTrace property to the ErrorRecord object. I use this function for error reporting:

function Write-Callstack([System.Management.Automation.ErrorRecord]$ErrorRecord=$null, [int]$Skip=1)
{
    Write-Host # blank line
    if ($ErrorRecord)
    {
        Write-Host -ForegroundColor Red "$ErrorRecord $($ErrorRecord.InvocationInfo.PositionMessage)"

        if ($ErrorRecord.Exception)
        {
            Write-Host -ForegroundColor Red $ErrorRecord.Exception
        }

        if ((Get-Member -InputObject $ErrorRecord -Name ScriptStackTrace) -ne $null)
        {
            #PS 3.0 has a stack trace on the ErrorRecord; if we have it, use it & skip the manual stack trace below
            Write-Host -ForegroundColor Red $ErrorRecord.ScriptStackTrace
            return
        }
    }

    Get-PSCallStack | Select -Skip $Skip | % {
        Write-Host -ForegroundColor Yellow -NoNewLine "! "
        Write-Host -ForegroundColor Red $_.Command $_.Location $(if ($_.Arguments.Length -le 80) { $_.Arguments })
    }
}

The Skip parameter lets me leave Write-Callstack or any number of error-handling stack frames out of the Get-PSCallstack listing.

Note that if called from a catch block, Get-PSCallstack will miss any frames between the throw site and the catch block. Hence I prefer the PS 3.0 method even though we have fewer details per frame.